feat(KubernetesPodOperator): Add support of container_security_context

[yyvess]

Allow to define a container security context on KubernetesPodOperator.

Why:
On clusters restricted with strong security policy, pods cannot be executed without disable privilege escalation.

About test :
I successfully run locally there tests : tests/providers/cncf/kubernetes/operators/test_kubernetes_pod.py
But I was not able to run tests kubernetes_tests/test_kubernetes_pod_operator.py :-(

[boring-cyborg]

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[yyvess]

@uranusjr please ☀️

[uranusjr]

You didn’t answer why you changed the security_context values in tests and how it affects compatibility.

[yyvess]

You didn’t answer why you changed the security_context values in tests and how it affects compatibility.

@uranusjr I was answed you .....
Changing only tests cannot affect compatibility 🙄
And as you can see all tests still green

I re-copy here my previous answer, please read it =>

@uranusjr Why => Because for me that was incorrect but isn't related to my main change as I write previously.
@potiuk I don't thinks that break anythings, the question is : why that test was not failed before my change ...

The variable security_context is injected on k8s.V1PodSpec =>
spec=k8s.V1PodSpec(..., security_context=self.security_context,

Look API documentation of K8s and you can see that security_context don't have a property securityContext =>

https://github.com/kubernetes-client/python/blob/master/kubernetes/docs/V1PodSpec.md
https://github.com/kubernetes-client/python/blob/master/kubernetes/docs/V1PodSecurityContext.md
It's seem that main issue is how the test is write. I am sure that on this test you can set security_context = {'hello': 'world'} and the test still green.

Perhaps we must change the type of security_context & container_security_context on class KubernetesPodOperator that is actually defined as Dict

security_context: Optional[Dict] = None, container_security_context: Optional[Dict] = None,

Should be more safer to declare it as is

security_context: Optional[k8s.V1PodSecurityContext] = None, container_security_context: Optional[k8s.V1SecurityContext] = None,

But should make on a different PR is you approved to change types

[uranusjr]

It's seem that main issue is how the test is write. I am sure that on this test you can set security_context = {'hello': 'world'} and the test still green.

This is the context I was looking for.

[boring-cyborg]

Awesome work, congrats on your first merged pull request!