CNG: Add graphicsmagick to the images
Summary
graphicsmagick is required for some of the favicon generation (for running pipelines, etc)
See: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/14497
This was added to omnibus a while ago: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/14497
Details
Once this change is in place, we can move the Design Management queues back to Kubernetes by reverting these MRs:
Edited by Jason Plum