Fix import pt_br locale in mastodon.jsx (#2011)

app/assets/javascripts/components/containers/mastodon.jsx

@@ -57,7 +57,7 @@ import uk from 'react-intl/locale-data/uk';
 import zh from 'react-intl/locale-data/zh';
 import bg from 'react-intl/locale-data/bg';
 import { localeData as zh_hk } from '../locales/zh-hk';
-import { localeData as pt_br } from '../locales/pt-br';
+import pt_br from '../locales/pt-br';
 import getMessagesForLocale from '../locales';
 import { hydrateStore } from '../actions/store';
 import createStream from '../stream';