Strip stable container size

[jan-kiszka]

Is there a reason to leave the debug artifacts (/usr/lib/debug) in stable builds? They are more than 500 MB large (unpacked).

It may also be worth to consider removing build tools (gcc & friends) again after installing all packages that may need during that step. To my understanding, the container is not intended to perform live update on it, rather to be replaced with a new build while keeping the persistent volumes.