Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /home/esecureh/public_html/magdemo/vendor/magento/module-ui/Test/Unit/Component/Form/FieldsetTest.php:21 Stack trace: #0 {main} thrown in /home/esecureh/public_html/magdemo/vendor/magento/module-ui/Test/Unit/Component/Form/FieldsetTest.php on line 21