Fix avatar/banner proxy (#8346)

* Fix avatar/banner proxy

Co-authored-by: mei23 <m@m544.net>

* use getAvatarUrl

* fix

* join avatar and banner to improve performance

* join

* Update hybrid-timeline.ts

* fix

Co-authored-by: mei23 <m@m544.net>
Co-authored-by: syuilo <Syuilotan@yahoo.co.jp>

packages/backend/src/server/index.ts

@@ -76,6 +76,8 @@ router.get('/avatar/@:acct', async ctx => {
 		usernameLower: username.toLowerCase(),
 		host: host === config.host ? null : host,
 		isSuspended: false,
+	}, {
+		relations: ['avatar'],
 	});
 
 	if (user) {