Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /home/app/htdocs/message_gateway_20231016/vendor/sebastian/diff/tests/DiffTest.php:20 Stack trace: #0 {main} thrown in /home/app/htdocs/message_gateway_20231016/vendor/sebastian/diff/tests/DiffTest.php on line 20