Debian Support

pulp_deb currently assumes that the "Suite" field in Release files always exists.

The following suggests that a "Suite" field is optional in Release files:
https://wiki.debian.org/DebianRepository/Format#Suite

Repositories without a "Suite" field exist in the wild:
http://deb.tuxedocomputers.com/ubuntu/dists/bionic/

Attempting to sync such repositories causes an error:

pulp: rq.worker:ERROR: KeyError: 'Suite'

Even if the KeyError is fixed, some fall back value must be provided since "Suite" is a mandatory DB field in pulp_deb.

Option 1: Find some suitable default fall back value when a remote has no "Suite" field in it's Release file.
Option 2: Do not make the DB field mandatory.

Option 1 is very easy to implement, option 2 would require migrations and could mess up the plugin logic...