AIRFLOW-4218 Support to Provide http args to K8executor while calling…

[andy-g14]

… k8 python client lib apis

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Jira

• My PR addresses the following [Airflow Jira]
  • https://issues.apache.org/jira/projects/AIRFLOW/issues/AIRFLOW-4218
  • In case you are fixing a typo in the documentation you can prepend your commit with [AIRFLOW-XXX], code changes always need a Jira issue.
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Description

Kubernetes Python client corev1 apis supports passing arguments like timeouts, async, etc. - https://github.com/kubernetes-client/python/blob/master/kubernetes/client/apis/core_v1_api.py
I would want to pass these arguments when using K8Executor mode by specifying args in kubernetes section of airflow.cfg as single line json dict string.

PS. args only used in K8executor and not in K8PodOperator.

• Here are some details about my PR, including screenshots of any UI changes:

Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:

Commits

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Documentation

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Code Quality

• Passes flake8

[feng-tao]

cc @dimberman