Backport #34703 by @lunny
Fix#34688
This PR will store the `publisher_id` of `release`(tag) table as
pusher's id. It could be a real userID or a system user id. If the user
is deleted, ghost will be replaced.
This PR will also correct the wrong user `Ghost` in the feeds and wrong
committer on tag list page if pushing a tag from an actions. Now the
behavior is the same as Github. Some codes are deleted because it tries
to get commit author as pusher which is not right.
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>