Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /home/app/htdocs/message_gateway/vendor/symfony/var-dumper/Tests/Test/VarDumperTestTraitTest.php:17 Stack trace: #0 {main} thrown in /home/app/htdocs/message_gateway/vendor/symfony/var-dumper/Tests/Test/VarDumperTestTraitTest.php on line 17