clean code

packages/app/src/server/models/in-app-notification.ts

@@ -4,13 +4,9 @@ import {
 import mongoosePaginate from 'mongoose-paginate-v2';
 
 import { getOrCreateModel } from '@growi/core';
-import Activity, { ActivityDocument } from './activity';
+import { ActivityDocument } from './activity';
 import ActivityDefine from '../util/activityDefine';
 
-import loggerFactory from '../../utils/logger';
-
-const logger = loggerFactory('growi:models:inAppNotification');
-
 export const STATUS_UNREAD = 'UNREAD';
 export const STATUS_UNOPENED = 'UNOPENED';
 export const STATUS_OPENED = 'OPENED';