Fatal error: Uncaught Error: Class 'Symfony\Contracts\EventDispatcher\Event' not found in /home/benjamincb/demos/acdg-site/vendor/nelmio/security-bundle/ContentSecurityPolicy/Violation/Event.php:25 Stack trace: #0 {main} thrown in /home/benjamincb/demos/acdg-site/vendor/nelmio/security-bundle/ContentSecurityPolicy/Violation/Event.php on line 25