fix: always install GPU drivers during bootstrapping

[jackfrancis]

Reason for Change:

This PR restores the previous behavior of always installing GPU drivers during bootstrapping. This has the side-effect of no longer supporting "airgap" scenarios, but it appears that simply apt-get download'ing the packages during VHD creation is not sufficient for providing that solution. I am speculating that files in /var/cache/apt/archives/ are regularly cleaned up based on the age of the files, which means that pre-downloaded apt packages in the VHD are only viable for a temporary period of time.

Issue Fixed:

Fixes #4631

Credit Where Due:

Does this change contain code from or inspired by another project?

• No
• Yes

If "Yes," did you notify that project's maintainers and provide attribution?

• No
• Yes

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Notes:

[jackfrancis]

cc @Michael-Sinz

[mboersma]

/lgtm

CI seems happy with this.

[Michael-Sinz]

We should look into what happened here - the files don't magically go away unless some code ran. The image does not run again until bootstrap is running so the image cache had to have been flushed somehow.

Either that or the actual packages changed somehow. Given that this image once did work, something changed to make it not work and that change had to be external to the image.