Fatal error: Uncaught Error: Class 'Symfony\Component\EventDispatcher\Tests\EventDispatcherTest' not found in E:\xampp\htdocs\www\key2\vendor\symfony\event-dispatcher\Tests\LegacyEventDispatcherTest.php:21 Stack trace: #0 {main} thrown in E:\xampp\htdocs\www\key2\vendor\symfony\event-dispatcher\Tests\LegacyEventDispatcherTest.php on line 21