fix: Forbid breaking the system

Unless the system has a file at /etc/apt/break-my-system

This change was made to Pop!_OS following requests that the prompt to remove essential packages be made more difficult to bypass. Users sometimes suffer from prompt fatigue, and ignore prompts such as this one. This change allows users to continue with operations that may remove essential packages, but they will need to create a file in order to do so.

The change will require additional translation for "This operation is not permitted because it will break the system." - I need some help with that, if the change is considered valuable for Debian.