fix(rt) typo in Japanese translation

fix typo in Japanese translation

Author: HIRANO-Satoshi

src/defaultTranslations/relative.time.ts

@@ -257,8 +257,8 @@ export const translations: DefaultTranslations = {
       day_in_plural: 'あと __count__ 日間',
       month_ago: '__count__ ヶ月前',
       month_ago_plural: '__count__ ヶ月前',
-      month_in: 'あと __count__ ヶ月前',
-      month_in_plural: 'あと __count__ ヶ月前',
+      month_in: 'あと __count__ ヶ月',
+      month_in_plural: 'あと __count__ ヶ月',
       year_ago: '__count__ 年前',
       year_ago_plural: '__count__ 年前',
       year_in: 'あと __count__ 年',