Fix gradle translation warnings

Created by: E3V3A

There are 4 gradle warnings about not having a default translation:

warning: string 'alert_silent_voice_sms_detected' has no default translation.
warning: string 'typevoice_data' has no default translation.
warning: string 'typevoice_header' has no default translation.
warning: string 'typevoice_title' has no default translation.