In resetbot.py, Servos 3 and 4 are never freed

In the function `reset_servos()`, Servos 3 and 4 are never reset:

```Python
def reset_servos():
    from XRPLib.servo import Servo
    # Turn off both Servos
    Servo.get_default_servo(1).free()
    Servo.get_default_servo(2).free()
```