Change string resource for face not detected error

    <!-- Message shown during face acquisition when the user is not front facing the sensor [CHAR LIMIT=50] -->

    <string name="face_acquired_poor_gaze">Please look more directly at your device.</string>

    <!-- Message shown during face acquisition when the user is not detected [CHAR LIMIT=50] -->

    <string name="face_acquired_not_detected">Can\u2019t see your face. Look at the phone.</string>

    <string name="face_acquired_not_detected">Position your face directly in front of the phone.</string>

    <!-- Message shown during face acquisition when the device is not steady [CHAR LIMIT=50] -->

    <string name="face_acquired_too_much_motion">Too much motion. Hold phone steady.</string>

    <!-- Message shown during face acquisition when the sensor needs to be recalibrated [CHAR LIMIT=50] -->