Add Ubuntu 18.04 package to the nightly upload pipeline
Add Ubuntu 18.04 package to the nightly upload pipeline

Changes from before 17247dd10d21897793b7f2c1d766d4d7d6a021d3 was merged
is that we don't build Ubuntu 18.04 for auto-deploy pipelines. This
commit just adds it to the regular nightly pipeline.

Signed-off-by: Balasankar "Balu" C <250a398eb3bfb9862062144cc742cc8f9bdd8d78@gitlab.com>

gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab,gitlabhq/omnibus-gitlab