[enhancement]: integration coverage wishlist

# Enhancement

Some wishlist items for increased test coverage:

- non-x86 -> the new shiny, arm64 + riscv maybe?
- Ubuntu + NetworkManager -> let's prempt desktop installer bugs-
- Ubuntu minimal -> smaller > bigger
- non-ubuntu coverage (Centos + Alpine?)

For all of these, the test can be simple: run cloud-init without user-data and check for recoverable errors.

This change request is for test coverage that isn't publicly available, but directly benefit the upstream project which is why I am filing it here.