Ability to add plugin to default `.` zone without overriding everything

[miroljub1995]

In values.yaml there is:

servers:
- zones:
  - zone: .
    use_tcp: true
  port: 53
  # -- expose the service on a different port
  # servicePort: 5353
  # If serviceType is nodePort you can specify nodePort here
  # nodePort: 30053
  # hostPort: 53
  plugins:
  - name: errors
  # Serves a /health endpoint on :8080, required for livenessProbe
  - name: health
    configBlock: |-
      lameduck 10s
  # Serves a /ready endpoint on :8181, required for readinessProbe
  - name: ready
  # Required to query kubernetes API for data
  - name: kubernetes
    parameters: cluster.local in-addr.arpa ip6.arpa
    configBlock: |-
      pods insecure
      fallthrough in-addr.arpa ip6.arpa
      ttl 30
  # Serves a /metrics endpoint on :9153, required for serviceMonitor
  - name: prometheus
    parameters: 0.0.0.0:9153
  - name: forward
    parameters: . /etc/resolv.conf
  - name: cache
    parameters: 30
  - name: loop
  - name: reload
  - name: loadbalance

I would like to just add a new plugin to this list, but without specifying this whole config for . zone on my end.