Remove support for prometheus.listen_address and prometheus.enable in gitlab.yml
Followup to !50500 (merged) and #227111. To be done in 14.0
See !50500 (diffs)
Release notes
The support for prometheus.listen_address and prometheus.enable has been removed from gitlab.yml. Please use prometheus.enabled and prometheus.server_address to set up Prometheus server that GitLab instance connects to. Please refer to https://docs.gitlab.com/ee/install/installation.html#prometheus-server-setup for details.
Edited by Changzheng Liu