Use git log name-status in get last commit (#16059)

* Improve get last commit using git log --name-status

git log --name-status -c provides information about the diff between a
commit and its parents. Using this and adjusting the algorithm to use
the first change to a path allows for a much faster generation of commit
info.

There is a subtle change in the results generated but this will cause
the results to more closely match those from elsewhere.

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-authored-by: Lauris BH <lauris@nix.lv>

modules/git/notes_nogogit.go

@@ -68,7 +68,7 @@ func GetNote(ctx context.Context, repo *Repository, commitID string, note *Note)
 	if err != nil {
 		return err
 	}
-	note.Commit = lastCommits[0]
+	note.Commit = lastCommits[path]
 
 	return nil
 }