Adding GitHub provider

[pateash]

closes: #20300

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Description

Adding Github provider based on Python SDK https://github.com/PyGithub/PyGithub
The SDK has many objects which can be viewed at https://pygithub.readthedocs.io/en/latest/github_objects.html

Users can create their own custom operators leveraging the PyGithub SDK, either by leveraging Hook directly or building their operator on GithubOperator by providing method and method_args from PyGithub
results can be further processed by implementing result_processor method, please look into GithubTagSensor for reference.

github_operator = GithubOperator( task_id='github-test', github_method="get_repo", github_method_args={'full_name_or_id': 'apache/airflow'}, result_processor=lambda r: r.full_name, dag=self.dag, ) 

[potiuk]

Very nice one!

I left a few comments, but it looks great already!

[pateash]

[pateash]

[pateash]

Hi @potiuk,
thanks for the comments, Please let me know if anything else needed.

[eladkal]

LGTM

@potiuk any further comments?

[potiuk]

Just in time for the January wave of Providers :)