shiritori/script/admin: force kana conversion before db import
shiritori/script/admin: force kana conversion before db import

Similar to b4f3aa7 we need to force kana conversion before importing
vocabulary in firebase.

Change-Id: I88bedbdbbba4e755be3187c79b642a8a0b80cd06

actions-on-google/actionssdk-shiritori-ja-nodejs