Fatal error: Uncaught Error: Class "Sabre\DAV\Auth\Backend\AbstractBasic" not found in D:\xampp\htdocs\pimcore\my-project\vendor\sabre\dav\lib\DAV\Auth\Backend\BasicCallBack.php:19 Stack trace: #0 {main} thrown in D:\xampp\htdocs\pimcore\my-project\vendor\sabre\dav\lib\DAV\Auth\Backend\BasicCallBack.php on line 19