Fix gutter highlights not matching diff hunks near excerpt boundaries (#25600)

Release Notes:

- Fixed gutter highlights not matching diff hunks in multibuffers in
some cases

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Co-authored-by: Max Brunsfeld <maxbrunsfeld@gmail.com>
198f56c763Cole Miller committed on 2/25/2025, 11:33:16 PM· committed by GitHubparentd68d858
4 files changedLine totals unavailable