Automatically mark as outdated old GitHub PR comments

Over on HBase, we use Yetus precommit on our PR builds. Often times, a PR is opened and as reviews come in, several commits are pushed to the PR branch. Also, we actually invoke Yetus three times – once for static checks and twice more for different JDK testing. Thus each push receives three comments from Yetus.

It would be great if Yetus could go back and mark as hidden/outdated all the old comments from previous builds. That way, reviewers can always find the current state, and folks interested in the discussion history aren't spending all their time scrolling past old automation reports.