Some have said disabling Sentry Mode will do that. I dunno. Here's what I found...
From the Model 3 User Manual:
If Model 3 is in Sentry Mode (see
How to Use Sentry Mode (Camera + App)), you must disable Sentry Mode before you can disable the Security alarm or the Tilt/Intrusion alarm.
Tilt/Intrusion (if equipped)
Depending on configuration, market region, and date of manufacture, your vehicle may not be equipped with this feature.
The Security Alarm must be on to enable Tilt/Intrusion.
Tilt/Intrusion sounds the alarm in your vehicle if Model 3 detects motion inside the cabin, or is moved or tilted (for example, with a tow truck or jack). To enable, touch Controls > Safety > Tilt/Intrusion.
The intrusion sensor automatically disables in situations where the climate control system is operating when you leave your vehicle. To override, you can manually turn the Tilt/Intrusion Sensor on again after choosing Keep Climate On, Dog, or Camp Mode.
The tilt/intrusion sensor automatically re-enables at the start of every drive cycle.
Note
If you plan to leave something that moves inside your locked vehicle, remember to turn off Tilt/Intrusion. If this setting is on, any motion detected inside Model 3 activates the intrusion alarm.