GH Actions: report CS violations in the PR
GH Actions: report CS violations in the PR

The cs2pr tool will allow to display the results from an action run in checkstyle format in-line in the PR code view, which should improve usability of the workflow results.

As the CS run is run in every test run in the matrix, passing the results on to CS2PR would result in violations being displayed multiple times, so using conditions to only pass the CS violations on to the PR for one of the runs.

Ref: https://github.com/staabm/annotate-pull-request-from-checkstyle

jrfnl/PHP_CodeSniffer,squizlabs/PHP_CodeSniffer,squizlabs/PHP_CodeSniffer,stronk7/PHP_CodeSniffer,jrfnl/PHP_CodeSniffer,squizlabs/PHP_CodeSniffer,jrfnl/PHP_CodeSniffer,stronk7/PHP_CodeSniffer,stronk7/PHP_CodeSniffer