message: Replace collection.count with collection.countDocuments
diff: @@ -92,9 +92,9 @@ export class NotificationController {
  return true;
  }
  if (!changedUnit) {
  - return (await Notification.count({'user': user._id, 'changedCourse': changedCourse._id})) === 0;
  + return (await Notification.countDocuments({'user': user._id, 'changedCourse': changedCourse._id})) === 0;
  }
  - return (await Notification.count({'user': user._id, 'changedUnit': changedUnit._id})) === 0;
  + return (await Notification.countDocuments({'user': user._id, 'changedUnit': changedUnit._id})) === 0;
  }
  async createNotification(user: IUser, text: string, changedCourse?: ICourse, changedLecture?: ILecture, changedUnit?: IUnit) {
  