Connect my checkstyle9.pl script to a action.

Connect the checkstyle9.pl script to a github action. This will provide
feedback to people submitting changes when the style is grossly wrong. And
can provide other automated feedback for the commit message in the future.
It already catches the github noreply author.

It pulls the full repo to do this. Optimizations welcome. After messing
with that for a few hours, I decided to punt and commit the slow, working
version and let someone else optimize from here.

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