Add custom dns manifests needed to connect to infra

[tssala23]

For cluster created using ESI there are some additional steps needed to connect the to the infra cluster due to our current network step up.
Adding the nerc-infra-routed network to each node is the first step.
The second is to set up custom dns on the cluster using these manifests to resolve the host name

[tssala23]

It would also require a patch to the dns operator that would look like this:

dns-patch.yaml

spec:
  servers:
  - name: mydomain
    zones:
    - mydomain.org
    forwardPlugin:
      policy: Random
      upstreams:
      - <cluster-ip>:8053 #oc -n custom-dns get svc --no-headers | awk '{ print $3 }'

However I am not sure exactly where that would go

[larsks]

You can use the service name instead of an ip address for specifying the custom server, like this:

  servers:
  - forwardPlugin:
      policy: Random
      upstreams:
      - custom-dns.custom-dns.svc.cluster.local:8053