Fatal error: Uncaught Error: Interface "Drupal\serialization\EntityResolver\EntityResolverInterface" not found in /home/www/drupal8/test/core/modules/serialization/src/EntityResolver/UuidResolver.php:11 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/modules/serialization/src/EntityResolver/UuidResolver.php on line 11