Code style improvements in JavaScript (#13159)

* JS-linter: fix trailing comma's

* Configure eslinter to ignore this onchange error.

app/javascript/mastodon/actions/accounts.js

@@ -106,7 +106,7 @@ export function fetchAccount(id) {
       dispatch,
       getState,
       db.transaction('accounts', 'read').objectStore('accounts').index('id'),
-      id
+      id,
     ).then(() => db.close(), error => {
       db.close();
       throw error;