Ubuntu 20.04 fails to soft-reboot after install

**Describe the issue**
Similar to #3320 and what @ivorscott described. After the Ubuntu 20.04 LTS Desktop install completes, you're prompted to reboot. However, after pressing reboot you're left at a black screen which will remain until the virtual machine is cold powered off/rebooted.
This also happens with Ubuntu Server 20.04, but this one is a blank screen with a blinking cursor.

Ubuntu 20.04 will boot fine after a cold boot, and I'm able to reboot from the installed disk. Maybe CD boot related issue?

**Configuration**
* UTM Version: 2.4.1
* OS Version: macOS Monterey 12.0.1
* Intel or Apple Silicon? Apple Silicon M1 Pro

**Crash log**
UTM did not crash

**Debug log**
Ubuntu 20.04 Desktop
[debug.log](https://github.com/utmapp/UTM/files/7611227/debug.log)

Ubuntu 20.04 Server
[debug2.log](https://github.com/utmapp/UTM/files/7611228/debug2.log)

**Upload VM**
Ubuntu 20.04 Desktop
[config.plist.txt](https://github.com/utmapp/UTM/files/7611231/config.plist.txt)

Ubuntu 20.04 Server
[config.plist.txt](https://github.com/utmapp/UTM/files/7611232/config.plist.txt)