github/ISSUE_TEMPLATE: Update issue form to remove checklist generation.

Update to the issue forms added earlier this year, that seem to generally
be working well.  Improvements in this commit:

- No longer generates TODO checklists in new issues.

- Issue bodies (and therefore email previews) no longer start with the same
  fixed checklist text for each new issue.

This work was funded through GitHub Sponsors.

Signed-off-by: Angus Gratton <angus@redyak.com.au>

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -11,19 +11,10 @@ body:
 
         * If you have a question \"How Do I ...?\", please post it on [GitHub Discussions](https://github.com/orgs/micropython/discussions/) or [Discord](https://discord.gg/RB8HZSAExQ) instead of here.
         * For missing or incorrect documentation, or feature requests, then please [choose a different issue type](https://github.com/micropython/micropython/issues/new/choose).
-  - type: checkboxes
+
-    id: terms
+        #### Existing issue?
-    attributes:
+
-      label: Checks
+        * Please search for [existing issues](https://github.com/micropython/micropython/issues) matching this bug before reporting.
-      description: |
-        Before submitting your bug report, please go over these check points:
-      options:
-      - label: |
-           I agree to follow the MicroPython [Code of Conduct](https://github.com/micropython/micropython/blob/master/CODEOFCONDUCT.md) to ensure a safe and respectful space for everyone.
-        required: true
-      - label: |
-          I've searched for [existing issues](https://github.com/micropython/micropython/issues) matching this bug, and didn't find any.
-        required: true
   - type: input
     id: port-board-hw
     attributes:
@@ -101,6 +92,17 @@ body:
       description: |
         Is there anything else that might help to resolve this issue?
       value: No, I've provided everything above.
+  - type: dropdown
+    id: code-of-conduct
+    attributes:
+      label: Code of Conduct
+      description: |
+        Do you agree to follow the MicroPython [Code of Conduct](https://github.com/micropython/micropython/blob/master/CODEOFCONDUCT.md) to ensure a safe and respectful space for everyone?
+      options:
+        - "Yes, I agree"
+      multiple: true
+    validations:
+      required: true
   - type: markdown
     attributes:
       value: |

.github/ISSUE_TEMPLATE/documentation.yml

@@ -9,19 +9,10 @@ body:
         This form is for reporting issues with the documentation or examples provided with MicroPython.
 
         If you have a general question \"How Do I ...?\", please post it on [GitHub Discussions](https://github.com/orgs/micropython/discussions/) or [Discord](https://discord.gg/RB8HZSAExQ) instead of here.
-  - type: checkboxes
+
-    id: terms
+        #### Existing issue?
-    attributes:
+
-      label: Checks
+        * Please search for [existing issues](https://github.com/micropython/micropython/issues) before reporting a new one.
-      description: |
-        Before submitting your bug report, please go over these check points:
-      options:
-      - label: |
-           I agree to follow the MicroPython [Code of Conduct](https://github.com/micropython/micropython/blob/master/CODEOFCONDUCT.md) to ensure a safe and respectful space for everyone.
-        required: true
-      - label: |
-          I've searched for [existing issues](https://github.com/micropython/micropython/issues) and didn't find any that matched.
-        required: true
   - type: input
     id: page
     attributes:
@@ -38,6 +29,17 @@ body:
         Please describe what was missing from the documentation and/or what was incorrect/incomplete.
     validations:
       required: true
+  - type: dropdown
+    id: code-of-conduct
+    attributes:
+      label: Code of Conduct
+      description: |
+        Do you agree to follow the MicroPython [Code of Conduct](https://github.com/micropython/micropython/blob/master/CODEOFCONDUCT.md) to ensure a safe and respectful space for everyone?
+      options:
+        - "Yes, I agree"
+      multiple: true
+    validations:
+      required: true
   - type: markdown
     attributes:
       value: |

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -15,19 +15,10 @@ body:
 
         * If you have a question \"How Do I ...?\", please post it on GitHub Discussions or Discord instead of here.
         * Could this feature be implemented as a pure Python library? If so, please open the request on the [micropython-lib repository](https://github.com/micropython/micropython-lib/issues) instead.
-  - type: checkboxes
+
-    id: terms
+        #### Existing issue?
-    attributes:
+
-      label: Checks
+        * Please search for [existing issues](https://github.com/micropython/micropython/issues) before opening a new one.
-      description: |
-        Before submitting your feature request, please go over these check points:
-      options:
-      - label: |
-           I agree to follow the MicroPython [Code of Conduct](https://github.com/micropython/micropython/blob/master/CODEOFCONDUCT.md) to ensure a safe and respectful space for everyone.
-        required: true
-      - label: |
-          I've searched for [existing issues](https://github.com/micropython/micropython/issues) regarding this feature, and didn't find any.
-        required: true
   - type: textarea
     id: feature
     attributes:
@@ -51,14 +42,32 @@ body:
          MicroPython aims to strike a balance between functionality and code size. Can this feature be optionally enabled?
 
          If you believe the usefulness of this feature would outweigh the additional code size, please explain. (It's OK to say you're unsure here, we're happy to discuss this with you.)
-  - type: checkboxes
+  - type: dropdown
     id: implementation
     attributes:
       label: Implementation
+      description: |
+        What is your suggestion for implementing this feature?
+
+        (See also: [How to sponsor](https://github.com/sponsors/micropython#sponsors), [How to submit a Pull Request](https://github.com/micropython/micropython/wiki/ContributorGuidelines).)
       options:
-      - label: I intend to implement this feature and would submit a Pull Request if desirable.
+        - I hope the MicroPython maintainers or community will implement this feature
-      - label: I hope the MicroPython maintainers or community will implement this feature.
+        - I intend to implement this feature and would submit a Pull Request if desirable
-      - label: I would like to [Sponsor](https://github.com/sponsors/micropython#sponsors) development of this feature.
+        - I would like to sponsor development of this feature
+      multiple: true
+    validations:
+      required: true
+  - type: dropdown
+    id: code-of-conduct
+    attributes:
+      label: Code of Conduct
+      description: |
+        Do you agree to follow the MicroPython [Code of Conduct](https://github.com/micropython/micropython/blob/master/CODEOFCONDUCT.md) to ensure a safe and respectful space for everyone?
+      options:
+        - "Yes, I agree"
+      multiple: true
+    validations:
+      required: true
   - type: markdown
     attributes:
       value: |

.github/ISSUE_TEMPLATE/security.yml

@@ -9,21 +9,11 @@ body:
 
         1. For issues that are readily exploitable or have high impact, please email contact@micropython.org instead.
         1. If this is a question about security, please ask it in [Discussions](https://github.com/orgs/micropython/discussions/) or [Discord](https://discord.gg/RB8HZSAExQ) instead.
-  - type: checkboxes
+
-    id: terms
+        #### Existing issue?
-    attributes:
+
-      label: Checks
+        * Please search for [existing issues](https://github.com/micropython/micropython/issues) before reporting a new one.
-      description: |
+
-        Before submitting your bug report, please go over these check points:
-      options:
-      - label: |
-           I agree to follow the MicroPython [Code of Conduct](https://github.com/micropython/micropython/blob/master/CODEOFCONDUCT.md) to ensure a safe and respectful space for everyone.
-        required: true
-      - label: I wish to report a specific security issue that is **not readily exploitable and does not have high impact** for MicroPython developers or users.
-        required: true
-      - label: |
-          I've searched for [existing issues](https://github.com/micropython/micropython/issues) and didn't find any that matched.
-        required: true
   - type: input
     id: port-board-hw
     attributes:
@@ -57,3 +47,14 @@ body:
         * How does the attacker exploit this issue?
     validations:
       required: true
+  - type: dropdown
+    id: code-of-conduct
+    attributes:
+      label: Code of Conduct
+      description: |
+        Do you agree to follow the MicroPython [Code of Conduct](https://github.com/micropython/micropython/blob/master/CODEOFCONDUCT.md) to ensure a safe and respectful space for everyone?
+      options:
+        - "Yes, I agree"
+      multiple: true
+    validations:
+      required: true