public function delete(Request $request, Department $department)
 {
     $this->authorize('delete-department');
     $event = $department->event;
     $department->delete();
     event(new EventChanged($event, ['type' => 'department', 'status' => 'deleted']));
     $request->session()->flash('success', 'Department has been deleted.');
     return redirect('/event/' . $event->id);
 }