Consider updating containers to bookworm base image

[costasd]

Hello,

since bookworm was released last year, bullseye has become the oldstable - while not pressing right now, security support for bullseye (and relevant images) will cease at some (not very far) point.

Would be good to move to bookworm earlier than that, to allow ample time for any bugfixes or any changes needed for package names, scripts etc.

Thanks!