Proposal: Mirror chart images to external registry

Summary

GitLab charts and images are stored on GitLab.com registry.

If GitLab.com has downtime or a maintenance window etc that affects these services, these charts and images are not available until the GitLab.com service is up again.

This could impact our Self-managed customers that deployed GitLab using these charts.

Proposal

Mirror charts and images on an external registry in a manner to the Runner image hosting discussed in this issue.

Alternative

We do have an issue to enable the ability to configure registry hosts. This will allow customers to self-host their own registry.