Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in /var/www/magento/html/app/code/Amasty/Rules/Test/Integration/Model/Discount/BaseDiscount.php:14 Stack trace: #0 {main} thrown in /var/www/magento/html/app/code/Amasty/Rules/Test/Integration/Model/Discount/BaseDiscount.php on line 14