Switch to a non-NIH upgrade system

In our 2020-2022 roadmap, we've added 1 big thing among this one, #10491 (closed), and #14567.

Subtasks

#15277

Related issues

https://gitlab.tails.boum.org/tails/blueprints/-/wikis/Faster_builds
Blocks #7499
I part of that, it would be great to give an option to rollback an upgrade to the previous version. Users are rightfully adverse to upgrades (think Tails 5.8).

Edited Jan 23, 2023 by sajolida

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