Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in /var/www/usonboard.com/vendor/microsoft/microsoft-graph-core/tests/Tasks/PageIteratorTest.php:21 Stack trace: #0 {main} thrown in /var/www/usonboard.com/vendor/microsoft/microsoft-graph-core/tests/Tasks/PageIteratorTest.php on line 21