Fatal error: Uncaught Error: Class 'Symfony\Component\HttpKernel\HttpKernel' not found in /home/app/htdocs/message_gateway/vendor/symfony/http-kernel/Tests/TestHttpKernel.php:21 Stack trace: #0 {main} thrown in /home/app/htdocs/message_gateway/vendor/symfony/http-kernel/Tests/TestHttpKernel.php on line 21