Accept /branch: and /cherry-pick: commands

[Sh0g0-1758]

Fixes: #64803

PR SUMMARY: Updated Regex to now accept colon endings in GitHub automation.

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[Sh0g0-1758]

I hope the number of commits can be overlooked. Ran into some rebasing issues. Added a PR summary for the merge commit.

[Sh0g0-1758]

Any idea why the build is failing? I have just changed the py regex. Please correct me if I am wrong but I don't think the build fail is caused by my changes.