def update_refresh_tokens(mrrt)
      fail ArgumentError, 'Token must contain an MRRT.' unless mrrt.mrrt?
      @token_cache.find.each do |entry|
        entry.refresh_token = mrrt.refresh_token if mrrt.can_refresh?(entry)
      end
    end
def update_refresh_tokens(mrrt)
      fail ArgumentError, 'Token must contain an MRRT.' unless mrrt.mrrt?
      @token_cache.find.each do |entry|
        entry.refresh_token = mrrt.refresh_token if mrrt.can_refresh?(entry)
      end
    end
Updates the refresh tokens of all tokens in the cache that match a given
 MRRT.

 @param CachedTokenResponse mrrt
   A new MRRT containing a refresh token to update other matching cache
   entries with.