Fatal error: Uncaught Error: Interface "Symfony\Component\HttpKernel\HttpKernelInterface" not found in /home/www/drupal8/test/core/lib/Drupal/Core/DrupalKernelInterface.php:15 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Core/DrupalKernelInterface.php on line 15