How do I enable grafana after upgrading?

I have been running GitLab Enterprise Edition for a while and perform updates semi-regularly. One of the new features of the 12.x version is that Grafana is bundled with the Omnibus version.

How do I enable that? I recently updated all the way to GitLab Enterprise Edition 12.8.1-ee and can navigate to https://repos.mydomain.com/-/grafana, but I get a 404 message. Reading through the docs, I see a lot of settings mentioned that have the following format grafana['enable'].

Unfortunately, my /etc/gitlab/gitlab.rb doesn’t have a single instance of grafana in it.

This leads me to believe that a simple apt get to upgrade like I have been doing isn’t sufficient to get all the new features.

How can I properly upgrade my install & get all new features and settings during the upgrade? I’d like to migrate from a stand-alone instance of grafana and use the one bundled with GitLab.