Fatal error: Uncaught Error: Class "Drupal\BuildTests\Framework\BuildTestBase" not found in /home/qcsvlel/www/core/tests/Drupal/BuildTests/Composer/ComposerBuildTestBase.php:15 Stack trace: #0 {main} thrown in /home/qcsvlel/www/core/tests/Drupal/BuildTests/Composer/ComposerBuildTestBase.php on line 15