PR Summary

This PR improves the checks around release notes in pull requests by updating the error message in the release notes checking script. The new message clarifies that, aside from the internal label (which does not require release notes), all other pull requests must include a descriptive release notes section.

Additionally, the PR modifies the GitHub Action workflow for release notes checks by changing the permission for pull-requests from read to write. This adjustment likely enables the workflow to create issue comments or perform other write operations on pull request objects, ensuring that the updated message can be correctly posted as a comment on the PR.

Test Suggestions

• Verify that a pull request with the required non-internal label but missing a valid release notes description triggers the new error message.
• Test that a pull request labeled internal bypasses the requirement for a release notes description.
• Check that the GitHub Action workflow successfully posts an issue comment when the release notes check fails.
• Ensure that the workflow's elevated pull-requests permission does not introduce any unintended side effects by validating the scope of its access.

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