Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in C:\sites\wasalnah.sabti-h.com\vendor\symfony\mime\Tests\Part\MessagePartTest.php:21 Stack trace: #0 {main} thrown in C:\sites\wasalnah.sabti-h.com\vendor\symfony\mime\Tests\Part\MessagePartTest.php on line 21