Fatal error: Uncaught Error: Interface "Drupal\Core\Entity\EntityInterface" not found in /home/www/drupal8/test/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php:13 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Core/Config/Entity/ConfigEntityInterface.php on line 13