make configurable boot-assessment checks

[davidcassany]

Part of rancher/elemental#1263

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 69.56522% with 7 lines in your changes are missing coverage. Please review.

Project coverage is 72.36%. Comparing base (c0f39f2) to head (3fc254c). Report is 1 commits behind head on main.

Files	Patch %	Lines
pkg/action/install.go	62.50%	2 Missing and 1 partial :warning:
pkg/action/reset.go	25.00%	2 Missing and 1 partial :warning:
pkg/features/features.go	85.71%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2018 +/- ## ========================================== + Coverage 72.34% 72.36% +0.01% ========================================== Files 76 76 Lines 8992 9009 +17 ========================================== + Hits 6505 6519 +14 - Misses 1944 1946 +2 - Partials 543 544 +1 ```

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[davidcassany]

The fallback test new logic tests the following: upgrades to a broken system:

1. Upgrades to a broken system, the new OS can't boot which causes a reboot to passive
2. Rebooting to passive succeeds, then from there it upgrades to a system including a checker that always fails. So after actually rebooting to active will reboot again after 5 failed attempts to pass the checker.
3. The reboot sequence will then attempt to boot to the broken system, which will fail again. Then the boot-assessment logic in grub will select the next system, which the snapshot installed during installation.
4. The former installed image will successfully boot and detect it booted into passive.