Move gitlab.yml generation to a template and have configmaps use that
Currently, we set gitlab.yml file using configmaps on sidekiq, unicorn and task-runner pods. So, it is 3 files we need to update if we need to add a field to gitlab.yml (if the field is needed for all of them). While I agree that not all pods require all the content in gitlab.yml, I still think it is good to have a SSOT for gitlab.yml and have the configmaps just use that. Maybe make it a template?