git: Add CHERRY_PICK_HEAD to the list of merge heads (#26145)

Attempt to fix an issue where conflicts from a cherry-pick don't get
cleared out of the git panel after being resolved.

Release Notes:

- Git Beta: Fixed resolution of conflicts from cherry-picks not being
reflected in the git panel
5daadc0d30Cole Miller committed on 3/5/2025, 10:31:45 PM· committed by GitHubparent431727f
2 files changedLine totals unavailable