Quote the SuppressWarnings value so PHPStan can parse it

PHPStan parses an unquoted @SuppressWarnings value as an expression and fails
on the dot in PHPMD.UnusedFormalParameter. The quoted form is valid PHPMD and
parses cleanly, so both analysers pass.

Author: rodchristiansen

app/Providers/AuthServiceProvider.php

@@ -91,7 +91,7 @@ class AuthServiceProvider extends ServiceProvider
      *
      * @return void
      *
-     * @SuppressWarnings(PHPMD.UnusedFormalParameter)
+     * @SuppressWarnings("PHPMD.UnusedFormalParameter")
      */
     public function boot()
     {