It’s not the SmartApp but rather the DTH that control the lock features. You’ll need a custom lock DTH to access those features from SmartThings or like jkp said you can do it physically on lock itself if you just want to toggle it once and be done with it.
Schlage -> 6 digit programming code -> Press 5 to toggle the beeper (1 beep enabled, 2 beeps disbaled)