It was discovered after reenabling unattended upgrades of grub-pc that a
small number of machines (12 out of 95) could not perform the upgrade
because of a missing debconf parameter.

Adding an extra step to the install procedure should help ensure we
don't hit this issue going forward.

This could likely be automated at least for ganeti instances, via the
grub hook: since we already run `grub-install` there, we already have
the correct block device address to install GRUB to.

We are looking into replacing Lektor altogether in
TPA-RFC-37 (tpo/web/team#42), so it is better to stop working on this
as it's a significant undertaking.

We can reopen this discussion if we decide to stick with Lektor in the
end.

Closes: tpo/web/team#28

I couldn't find it the first time.

We don't have the cycles to process this right now, and al made a good
point that major donors specifically want this product, so we'd be
hard-pressed to just ditch it. It feels like a waste of time.

Closes: tpo/web/donate-static#75

This enables a new capability for which support was added in Ganeti
3.0.0: postcopy-ram migration support. Enabling this flag allows Ganeti
to automatically switch to postcopy-ram when precopy-ram migration is
not completing fast, allowing us to migrate very busy machines much more
rapidly and without human intervention (eg. no need to SIGSTOP gitlab
processes when migrating gitlab-02).

https://github.com/ganeti/ganeti/blob/master/NEWS#automatic-postcopy-migration-handling-for-kvm-guests
https://wiki.qemu.org/Features/PostCopyLiveMigration

This is mostly so I can document the new ~Survey tag in GitLab.

I just upgraded a workstation to bookworm by mistake like this. Oops.

it is more readable that way

Closes team#40853