Adapt our infrastructure to be able to handle tons of packages

Originally created by @intrigeri on #6303 (Redmine)

When we’ll import all the packages we need into our own APT repository, it’s unlikely that our various cronjobs etc. handle the load as is. Same for our fail-over and backup systems.

Parent Task: tails#9489 (closed)

Subtasks

• #10851 (closed)

Related issues

• Related to tails#9508 (closed)
• Blocked by #6295 (closed)