Release v0.5.0 python client library validation

[jasoonn]

Why are these changes needed?

1. Verify the built clusters in examples of the python client library are functional.
2. Remove init containers in template because there will be default init container in v0.5.0(#973).

Basic flow for verification cluster

Cover the following examples: use-builder.py, use-director.py, use-raw-config_map_with-api.py, use-raw-with-api.py, use-utils.py.

1. Setup Ray operator

   kind create cluster
   helm repo add kuberay https://ray-project.github.io/kuberay-helm/ 
   helm repo update
   helm install kuberay-operator kuberay/kuberay-operator --version 0.5.0-rc.0
   

2. Comment out the cluster deletion section in the python file.
   

   kuberay/clients/python-client/examples/use-builder.py

   Lines 66 to 72 in 00dc45a

   	if "items" in kube_ray_list:
   	for cluster in kube_ray_list["items"]:
   	print("deleting raycluster = {}".format(cluster["metadata"]["name"]))
   	my_kuberay_api.delete_ray_cluster(
   	name=cluster["metadata"]["name"],
   	k8s_namespace=cluster["metadata"]["namespace"],
   	)

3. Run the example
   python3 use-builder.py

4. Submit a simple ray job to the cluster
   

5. Port forwarding
   

6. Check cluster dashboard
   

Additional steps for complete-example.py

Because there is an update of cluster in complete-example.py, we need to verify whether the cluster information is modified as expected. Hence, input() is put before the call of modification cluster API(line 62 in complete-example.py) to pause the execution of the example, and two Ray jobs are submitted before and after the modification to see whether the cluster resource is updated as exected.

Related issue number

Checks

• I've made sure the tests are passing.
• Testing Strategy
  • Unit tests
  • Manual tests
  • This PR is not tested :(