In manual merge detected changes, the pushing user should be the
de-facto author of the merge, not the committer. For ff-only merges, the
author (PR owner) often have nothing to do with the merger. Similarly,
even if a merge commit exists, it does not indicate that the merge
commit author is the merger. This is especially true if the merge commit
is a ff-only merge on a given branch.
If pusher is for some reason unavailable, we fall back to the old method
of using committer or owning organization as the author.
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Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
