[BB-313] - Updating to latest containers from IB, fixing metrics exposition(?) for gitlab, removing prometheus install

Updating container images to their latest available IronBank counterparts. Adding options for gitlab metrics to expose on port and be available at /metrics for prometheus/istio-service-monitors. ** removing prometheus install as prometheus is installed in monitoring namespace for bootstraps.

** gitlab-exporter container image from IronBank is not fully complete, so metrics are only available at /sidekiq URL on port 9168. /metrics URL returns HTTP/500.