kernel updates require two reboots

### What Happened?

For some reason - and unique in the Linux world - the new versions of Appcenter require **two** reboots when there are kernel updates in the queue. This is _highly unusual_.

### Steps to Reproduce

1. Open Appcenter to see available updates.
2. If you see the linux kernel under "System updates" - bingo!
3. Hit "Update all" - note that "System updates" has a "Download" button on the right side, rather than "Update".
4. The Appcenter will prompt you to reboot - do it.
5. After a reboot, the Appenter will again show a notification that updates are available.
6. Open Appcenter and see that "System updates" are still there and the linux kernel is still among them.
7. Hit update (again).
8. You will be (again) prompted to reboot. Again, do it.
9. After the second reboot there are _finally_ no more updates.

### Expected Behavior

Kernel updates have always required only one reboot. It's a nice tradition to keep.

### OS Version

7.x (Horus)

### Software Version

Latest release (I have run all updates)

### Log Output

_No response_

### Hardware Info

_No response_