Fatal error: Uncaught Error: Class "Symfony\Contracts\EventDispatcher\Event" not found in C:\xampp\htdocs\slip\laravel-webhooks\vendor\symfony\mailer\Event\FailedMessageEvent.php:20 Stack trace: #0 {main} thrown in C:\xampp\htdocs\slip\laravel-webhooks\vendor\symfony\mailer\Event\FailedMessageEvent.php on line 20