Upgrade to PHP_CodeSniffer 4 (#7993)

https://github.com/PHPCSStandards/PHP_CodeSniffer/wiki/Version-4.0-User-Upgrade-Guide
A couple of rules have changed name. Exclusion paths have slightly changed behaviour.
Main change is that it was unhappy with our i18n header comments, so minor edit there, since that rule kind of makes sense the rest of the time

tests/app/Models/UserQueryTest.php

@@ -2,6 +2,7 @@
 declare(strict_types=1);
 
 use PHPUnit\Framework\TestCase;
+
 /**
  * Description of UserQueryTest
  */