Fatal error: Uncaught Error: Class 'Google\Cloud\Core\Testing\System\SystemTestCase' not found in /home/app/htdocs/lidia/vendor/google/cloud/tests/system/PubSub/PubSubTestCase.php:23 Stack trace: #0 {main} thrown in /home/app/htdocs/lidia/vendor/google/cloud/tests/system/PubSub/PubSubTestCase.php on line 23