[AIRFLOW-XXXX] Remove unnecessary docstring in AWSAthenaOperator

[coopergillan]

EDIT - here is the updated PR description: query_execution_id is returned by execute, which means that the default behavior is that it will be xcom_pushed. While this can be overridden since this is a subclass of BaseOperator and this is an argument that is accepted, it need not be mentioned in the docstring here since it is referring to default behavior.

Old PR description for transparency:
Since query_execution_id is now returned by execute, it will be xcom
pushed by default, meaning do_xcom_push is no longer needed and should
not be mentioned in the docstring.

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[jhtimmins]

This change looks good. The earliest history I see for this file is in November 2019, at which point the Athena operator did not make use of do_xcom_push. It's not immediately clear if it ever did use the variable, but it isn't now.

[turbaszek]

I think this is still valid because:

airflow/airflow/models/taskinstance.py

Lines 1035 to 1037 in 7a54418

	# If the task returns a result, push an XCom containing it
	if task_copy.do_xcom_push and result is not None:
	self.xcom_push(key=XCOM_RETURN_KEY, value=result)

[turbaszek]

If operator's execute method returns a result it doesn't mean that it will be always saved in XCom table. This will happen only if operator is used with do_xcom_push=True

[coopergillan]

Got it, that makes sense. This behavior seems to correspond to the super classes and not to this specific class, hence why I don't think it needs to be mentioned in the docstring. Does that make sense?

[coopergillan]

Here is the setting in BaseOperator on master. Since operator docstrings usually do not mention super class functionality, I think this could be removed. The behavior should be evident by looking at the super class and understanding that query_execution_id is the value in question that will or will not be xcom_pushed.

[turbaszek]

Since operator docstrings usually do not mention super class functionality, I think this could be removed.

With that I can agree. My point was that this part of the PR description is not true:

Since query_execution_id is now returned by execute, it will be xcom
pushed by default

[coopergillan]

Noted! Just updated the PR description and title to reflect the full context. Thanks for pointing that out!

[coopergillan]

@turbaszek - just rebased and cleaned up the wording a bit. Apologies that I didn't see your approval first. Please let me know if it still stands.