UTM crashes (or goes unresponsive) when Sidecar display disconnects

**Describe the issue**

When I have UTM VM running on a iPad Sidecar display, (just regular windows, not even full screen) UTM would crash when Sidecar connection crashes, or at the very least would go unresponsive when Sidecar disconnects.

**Configuration**
* UTM Version: 3.1.0 beta
* OS Version: 12.2.1
* Intel or Apple Silicon?: Apple Silicon (M1)

**Crash log**
[UTM-2022-02-21-115029.ips.zip](https://github.com/utmapp/UTM/files/8105833/UTM-2022-02-21-115029.ips.zip)

**Debug log**
[debug.log](https://github.com/utmapp/UTM/files/8106033/debug.log)

**Upload VM**
Not related to VM