Fatal error: Uncaught Error: Class "Drupal\Core\Config\Entity\ConfigEntityStorage" not found in /home/www/drupal8/test/core/modules/config/tests/config_test/src/ConfigTestStorage.php:11 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/modules/config/tests/config_test/src/ConfigTestStorage.php on line 11