Bugfix for cleanup-pods command

[humit0]

When getting cleanup pods list, it requires to have execution_date label.
But from the code, it does not set execution_date label when trigger by scheduler.

So I remove execution_date label when get pod list.

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[kaxil]

We can't just remove execution_date date alone as it will otherwise remove tasks from other execution_date or run_ids too.

We add a run_id or an execution_date to labels, see:

airflow/airflow/kubernetes/pod_generator.py

Lines 369 to 374 in aa27d9f

	if date:
	annotations['execution_date'] = date.isoformat()
	labels['execution_date'] = datetime_to_label_safe_datestring(date)
	if run_id:
	annotations['run_id'] = run_id
	labels['run_id'] = make_safe_label_value(run_id)

[humit0]

@kaxil From original code, it removes all success, evicted, and (failed & restartPolicy: Never) pods, not filter pod by execution_date or run_id.
So I think execution_date part is unnecessary.

[kaxil]

@kaxil From original code, it removes all success, evicted, and (failed & restartPolicy: Never) pods, not filter pod by execution_date or run_id. So I think execution_date part is unnecessary.

I will take another look later today or tomorrow