chore: Update fetch-depth comment

[keelerm84]

Summary

• Fix incorrect comment on fetch-depth in GitHub Actions workflow(s)
• The old comment implied fetch-depth: 0 was for getting only the current version, when it actually fetches full history

Test plan

• Verify CI workflows still pass

🤖 Generated with Claude Code

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Note

Low Risk
Comment-only change in CI configuration; no functional impact to builds or releases.

Overview
Updates the comment for actions/checkout’s fetch-depth: 0 in .github/workflows/release-please.yml to correctly state that full git history is required for changelog generation; no workflow behavior changes.

^{Written by Cursor Bugbot for commit 1a27182. This will update automatically on new commits. Configure here.}