Promote spark from contribution to application

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master

@rimolive do you remember who wanted to help with the spark operator? I think the main problem is that

it does not work with istio "sidecar.istio.io/inject": "true" https://github.com/kubeflow/manifests/blob/73cbecfe604e84dfc7c0851630a6eb5733022dea/contrib/spark/sparkapplication_example.yaml#L24C7-L24C41
We are missing a securitycontext in https://github.com/kubeflow/manifests/blob/73cbecfe604e84dfc7c0851630a6eb5733022dea/contrib/spark/sparkapplication_example.yaml and it should be upstreamed to the spark repository
```
securityContext:
  capabilities:
    drop:
      - ALL
  runAsUser: 185
  runAsGroup: 0
  runAsNonRoot: true
  allowPrivilegeEscalation: false
  seccompProfile:
    type: RuntimeDefault
```
We need to add runAsGroup:0 or 185 in the securitycontext of https://github.com/kubeflow/manifests/blob/master/contrib/spark/spark-operator/base/kustomization.yaml and we need to upstream it
We need a synchronization script in /hack derived from the current makefile

kubeflow / manifests