cluster-addon-values are not templated

[chess-knight]

/kind bug

What steps did you take and what happened:

1. Create cluster-addon-values.yaml, e.g.:

values: |
  metrics-server:
    commonLabels:
      domain: "{{ .Cluster.spec.controlPlaneEndpoint.host }}"
      clusterAddonVersion: "<< .ClusterAddonVersion >>"

2. Run csctl create ...
3. cluster-addon-values.yaml asset is without change

What did you expect to happen:

values: |
  metrics-server:
    commonLabels:
      domain: "{{ .Cluster.spec.controlPlaneEndpoint.host }}"
      clusterAddonVersion: "v2"

Anything else you would like to add:
It was mentioned also in SovereignCloudStack/cluster-stacks#43 (comment)

Environment:

• csctl version: (use csctl version)
• OS (e.g. from /etc/os-release):