Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /home/esecureh/public_html/magdemo/vendor/magento/module-configurable-product/Test/Unit/Model/Product/VariationHandlerTest.php:30 Stack trace: #0 {main} thrown in /home/esecureh/public_html/magdemo/vendor/magento/module-configurable-product/Test/Unit/Model/Product/VariationHandlerTest.php on line 30