Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /home/esecureh/public_html/magdemo/vendor/magento/module-theme/Test/Unit/Controller/Adminhtml/Design/Config/SaveTest.php:31 Stack trace: #0 {main} thrown in /home/esecureh/public_html/magdemo/vendor/magento/module-theme/Test/Unit/Controller/Adminhtml/Design/Config/SaveTest.php on line 31