Add zuul-jobs for ubuntu-bionic
Add zuul-jobs for ubuntu-bionic

Start testing our jobs on ubuntu-bionic to ensure things work as
expected.

Change-Id: Ibf8005832d882295857dc1e07adf65984e0fb8ee
Depends-On: https://review.openstack.org/549635
Signed-off-by: Paul Belanger <e7139c8e6c4ea75cc1c287ce081b2dc0f3ab39ec@redhat.com>

openstack-infra/project-config,openstack-infra/project-config