feat: add support for coredns_affinity

[HoKim98]

What type of PR is this?

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/kind api-change
/kind bug
/kind cleanup
/kind design
/kind documentation
/kind failing-test
/kind feature
/kind flake

What this PR does / why we need it:

Hello, this PR just introduces coredns_affinity to fine-tune it's placement.
It's especially useful for edge clusters, which contain unstable nodes (e.g. wireless connection, power-off, etc).

The default value is same as-is.

coredns_affinity:
  podAntiAffinity:
    requiredDuringSchedulingIgnoredDuringExecution:
      - topologyKey: "kubernetes.io/hostname"
        labelSelector:
          matchLabels:
            k8s-app: kube-dns{{ coredns_ordinal_suffix }}
  nodeAffinity:
    preferredDuringSchedulingIgnoredDuringExecution:
      - weight: 100
        preference:
          matchExpressions:
            - key: node-role.kubernetes.io/control-plane
              operator: In
              values:
                - ""

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

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[ant31]

/ok-to-test

[tico88612]

@HoKim98 could you rebase this PR?