feat(service): add support for nodePort

[mueller-ma]

Closes #204

[mueller-ma]

I tried to follow the steps from CONTRIBUTING.md and deployt this version of the operator, but the CRDs didn't change. When I try to apply the following file, I get the error strict decoding error: unknown field "spec.resources.serviceSpec":

apiVersion: dragonflydb.io/v1alpha1
kind: Dragonfly
metadata:
  labels:
    app.kubernetes.io/name: dragonfly
    app.kubernetes.io/instance: dragonfly-sample
    app.kubernetes.io/part-of: dragonfly-operator
    app.kubernetes.io/managed-by: kustomize
    app.kubernetes.io/created-by: dragonfly-operator
  name: dragonfly-sample
spec:
  replicas: 2
  resources:
    requests:
      cpu: 500m
      memory: 500Mi
    limits:
      cpu: 600m
      memory: 750Mi
    serviceSpec:
      type: NodePort
      nodePort: 20001

Did I miss any file that needs to be updated as well? I looked at the PR #187 for this change.

[Abhra303]

@mueller-ma, you have put serviceSpec under resources. serviceSpec should be at the same level as resources.

[mueller-ma]

Thanks for that hint. With a valid yaml Dragonfly manifest, I was able to deploy a dragonfly instance, that uses a fixed node port.