ci: Auto-apply 27.lts cherry-pick label to main PRs

[oxve]

Introduce automatic labeling for pull requests merged into the main.
Changes originating on main are automatically identified as
candidates for cherry-picking to the 27.lts release branch
Additionally, update the known cherry-pick target branches to include
27.lts.1+ for other originating branches.

Bug: 484351320

[github-actions]

🤖 Gemini Suggested Commit Message

---

ci: Auto-apply 27.lts label for main PRs

Introduce automatic labeling for pull requests merged into the main
branch to include the 'cp-27.lts.1+' cherry-pick label. This ensures
that changes originating on main are automatically identified as
candidates for cherry-picking to the 27.lts release branch, improving
the efficiency and consistency of the release branching process.
Additionally, update the known cherry-pick target branches to include
27.lts.1+.

Bug: 484351320

---

💡 Pro Tips for a Better Commit Message:

1. Influence the Result: Want to change the output? You can write custom prompts or instructions directly in the Pull Request description. The model uses that text to generate the message.
2. Re-run the Generator: Post a comment with: /generate-commit-message

[gemini-code-assist]

Code Review

The pull request introduces a new GitHub Actions configuration file to automatically apply the cp-27.lts.1+ label to all pull requests merged into the main branch. This change seems straightforward and aims to streamline the cherry-picking process for the 27.lts.1+ branch. I've reviewed the changes and found one area for improvement regarding the glob pattern.

[gemini-code-assist]

Using any-glob-to-any-file: '**' will apply the label to any change, which might be overly broad. If the intention is to only apply this label to changes that are relevant for cherry-picking to 27.lts.1+, consider a more specific glob pattern. For example, if only changes within a certain directory or with a specific file extension are relevant, the glob should reflect that. If the intent is truly for all files, then this is acceptable, but it's worth double-checking the scope.