Fix minimum token permissions for workflows that perform git push

[Copilot]

This PR ensures that all GitHub workflows performing git push operations have the required contents: write permission with appropriate explanatory comments.

Changes Made

Updated .github/workflows/auto-spotless-apply.yml to add an explanatory comment to the existing contents: write permission:

permissions:
  contents: write  # required for pushing changes
  pull-requests: write

Analysis Summary

All workflows that perform git push operations were analyzed:

• ✅ auto-spotless-apply.yml - FIXED: Added "# required for pushing changes" comment
• ✅ backport.yml - Already had "# for Git to git push" comment
• ✅ prepare-patch-release.yml - Already had "# for Git to git push" comment
• ✅ prepare-release-branch.yml - Already had "# for Git to git push" comment
• ✅ release.yml - Already had "# for git push to PR branch" comment

The repository now meets the requirement that all workflows performing git push have contents: write permission with appropriate explanatory comments for compliance and clarity.

Fixes #116.

---

💬 Share your feedback on Copilot coding agent for the chance to win a $200 gift card! Click here to start the survey.