Fatal error: Uncaught Error: Class "App\Extension\AbstractUpgradeStep" not found in C:\xampp\htdocs\gnu_7\g7\upgrades\Upgrade_7_0_0.php:29 Stack trace: #0 {main} thrown in C:\xampp\htdocs\gnu_7\g7\upgrades\Upgrade_7_0_0.php on line 29