Automate PR with release notes draft

[yuxiang-zhang]

Description

Previously for new releases, the maintainers have to manually copy release notes from drafts, commit the file and open PR.

This PR automates that process by having the same workflow update a PR for the new release notes.

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the userdocs directory)
• Manually tested
• Made sure the title of the PR is a good description that can go into the release notes
• (Core team) Added labels for change area (e.g. area/nodegroup) and kind (e.g. kind/improvement)

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟

[a-hilaly]

Nice!
/lgtm