"auth_client_using_bad_version_title" is translated here but not found in default locale

On the top of your strings file, change the <resources> to this:

<resources tools:ignore="ExtraTranslation" xmlns:tools="http://schemas.android.com/tools">

Looks like some caching issue of Android Studio. For me File -> Invalidate caches/restarts fixed the issue.

Goto

Window->preferences->Android->Lint Error Checking -->Correctness: Messages--> Extra Translations ------------>make it Fatal to Warning