My use case is that, I have a forked version of gitlab hosted on gitlab.example.com. which has so modification. This repo constantly merging/rebasing from upstream (gitlab-org/gitlab). How can I install/upgrade this forked version using cloud native method (helm chart)?
You need to build your own images and use that images in the Helm Chart values.yaml
can I fork any existing Helm Chart values.yaml that the official gitlab is maintaining?