Automated method to deploy and configure a database for the Registry (Charts)

Context

This was identified as a requirement to enable the implementation of auto-deployments for the Container Registry (gitlab-org&7998 (closed)), identified as task B in the overall plan.

Problem

After further discussion about this in gitlab-org/container-registry#676 (closed) (see this thread), it's now clear that we lack an automated method to deploy and configure a database for the Registry in Charts.