build: Updating mediawiki/mediawiki-codesniffer to 14.1.0
The following sniffs now pass and were enabled:
- MediaWiki.Commenting.FunctionComment.MissingReturn
And moved phpcs.xml to .phpcs.xml (T177256).
Change-Id: I8a5b40a1d05d42c7e2a7febd5a05fdddbc8913f0