No Warewulf prompt in chroot with Debian image (and custom Debian based images)

Debian overrides the prompt by setting **PS1** variable in `/etc/bash.bashrc`

A possible solution:
```
diff /etc/bash.bashrc /etc/bash.bashrc.orig 
20a21
> if ! [[ "${PS1}" =~ "Warewulf" ]]; then
21a23
> fi
```

In Ubuntu also `/root/.bashrc` is overriding **PS1**, and it will need to have additional modifications similar to `/etc/bash.bashrc` 