Fatal error: Uncaught Error: Class "Illuminate\Support\MultipleInstanceManager" not found in C:\xampp\htdocs\astra-backoffice\vendor\laravel\framework\tests\Integration\Support\Fixtures\MultipleInstanceManager.php:7 Stack trace: #0 {main} thrown in C:\xampp\htdocs\astra-backoffice\vendor\laravel\framework\tests\Integration\Support\Fixtures\MultipleInstanceManager.php on line 7