fix bug on filemounts update

ot_admin/Classes/Controller/SiteController.php

@@ -2377,7 +2377,7 @@ class SiteController extends ActionController
         $rows = $statement->fetchAllAssociative() ?: [];
         $files = [];
         foreach ($rows as $row) {
-            $files[] = $row[0];
+            $files[] = $row['uid'];
         }
 
         $mainGroup = self::IS_PRODUCT_PREMIUM[$userData['product']] ? self::BEGROUP_EDITOR_PREMIUM : self::BEGROUP_EDITOR_STANDARD;