email: solve install conflicts
Solve install conflicts (exim4) by removing installed conflicting packages before installation of email server.
Other likely install conflicts have been discarded: msmtp, nullmailer, sendmail. qmail and smail are less likely since they are missing in Bullseye.
Pending: (To be fixed and rebased later or even in another merge request):
- Removing conflicting packages without user notice might be too rough. A generic warning should help.
- Mock OS calls (?).
Edited by Fioddor Superconcentrado