Fatal error: Uncaught Error: Class "OCP\Migration\SimpleMigrationStep" not found in /var/www/html/nextcloud/apps/files_external/lib/Migration/Version1015Date20211104103506.php:21 Stack trace: #0 {main} thrown in /var/www/html/nextcloud/apps/files_external/lib/Migration/Version1015Date20211104103506.php on line 21