/**
  * @param $arr
  * @throws GroupNotFoundException
  */
 public function deleteGroup($arr)
 {
     try {
         if (is_numeric($arr)) {
             $group = Groups::findOrFail($arr);
         } else {
             $group = Groups::where("name", Str::lower($arr));
         }
         $group->delete();
     } catch (ModelNotFoundException $e) {
         throw new GroupNotFoundException(trans('user-management::messages.group_not_found'), [trans('user-management::messages.group_not_found')]);
     }
 }