Add extraServiceSpec option

[hrntknr]

Add a spec that is not defined as extraServiceSpec.

ref: https://github.com/itzg/minecraft-server-charts/pull/167

helm install minecraft oci://cr.i.hirano.work/library/minecraft --dry-run --debug

# Source: minecraft/templates/minecraft-svc.yaml
apiVersion: v1
kind: Service
metadata:
  name: minecraft-minecraft
  labels:
    app: minecraft-minecraft
    chart: "minecraft-4.9.5"
    release: "minecraft"
    heritage: "Helm"
    app.kubernetes.io/name: "minecraft"
    app.kubernetes.io/instance: minecraft-minecraft
    app.kubernetes.io/version: "4.9.5"
  annotations:
    {}
spec:
  type: ClusterIP
  ports:
  - name: minecraft
    port: 25565
    targetPort: minecraft
    protocol: TCP
  selector:
    app: minecraft-minecraft

cat values.yaml

minecraftServer:
  extraServiceSpec:
    ipFamilyPolicy: RequireDualStack

helm install minecraft oci://cr.i.hirano.work/library/minecraft --dry-run --debug --values values.yaml

# Source: minecraft/templates/minecraft-svc.yaml
apiVersion: v1
kind: Service
metadata:
  name: minecraft-minecraft
  labels:
    app: minecraft-minecraft
    chart: "minecraft-4.9.5"
    release: "minecraft"
    heritage: "Helm"
    app.kubernetes.io/name: "minecraft"
    app.kubernetes.io/instance: minecraft-minecraft
    app.kubernetes.io/version: "4.9.5"
  annotations:
    {}
spec:
  type: ClusterIP
  ports:
  - name: minecraft
    port: 25565
    targetPort: minecraft
    protocol: TCP
  selector:
    app: minecraft-minecraft
  ipFamilyPolicy: RequireDualStack