Fixed a reset password message in Japanese locales.

[seigo23]

Japanese locales has a small problem in devise_token_auth/config/locales/ja.yml

This 'request_reset_link_msg' is "下記のリンクからパスワードの変更 'を' できます" right now.

But this message is slightly strange for Japanese.

In this case, "下記のリンクからパスワードの変更 'が' できます". is natural.

This is very small problem,
But this message could be seen by users who use the web service.

And, Japanese are often suspicious of that web service if some messages has strange Japanese grammar.

ex.
"Was this web service developed by a dishonest dealer...??
I don't want to use that service, because
there is a possibility to get some computer virus from that service...."

So, I make a suggestion fixing this small grammatical mistakes.

[MaicolBen]

Thanks for fix, and great example! Use G Translator and makes sense