Fatal error: Uncaught Error: Class 'OxidEsales\TestingLibrary\UnitTestCase' not found in /www/shop/vendor/oxid-esales/gdpr-optin-module/Tests/Integration/ContactControllerTest.php:29 Stack trace: #0 {main} thrown in /www/shop/vendor/oxid-esales/gdpr-optin-module/Tests/Integration/ContactControllerTest.php on line 29