Adds a valkey helm remote and allowlists the operator/exporter images so the
valkey-operator install in argocd-apps resolves everything through artifactapi.
- Add config/remote_helm/valkey.yaml proxying https://valkey.io/valkey-helm
- Add valkey to the virtual/helm member list
- Allow ^valkey-io/ on the ghcr remote (operator image ghcr.io/valkey-io/valkey-operator)
- Allow ^oliver006/redis_exporter on dockerhub (Valkey metrics exporter)