Fix unreachable code errors in yandex provider

[jeff3071]

related: #53395

mypy warning: providers/yandex/src/airflow/providers/yandex/operators/dataproc.py:149: error: Statement is unreachable [unreachable]

caused by:

if services is None:
            services = []

services type hint: Iterable[str] was not allowed be None. mypy think if services is None: condition always false.

fix: add type hint None

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[boring-cyborg]

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[gopidesupavan]

i think you can remove this condition itself, https://github.com/apache/airflow/pull/53453/files#diff-f2fbaeacd7184aebb7503aa6285edf361283cb90c932e7709c01ab8dacc23d52R148, because the dataproc accepts None aswell https://github.com/yandex-cloud/python-sdk/blob/master/yandexcloud/_wrappers/dataproc/__init__.py#L68

So addting None type to services args seems fine.

[jeff3071]

i think you can remove this condition itself, https://github.com/apache/airflow/pull/53453/files#diff-f2fbaeacd7184aebb7503aa6285edf361283cb90c932e7709c01ab8dacc23d52R148, because the dataproc accepts None aswell https://github.com/yandex-cloud/python-sdk/blob/master/yandexcloud/_wrappers/dataproc/__init__.py#L68

So addting None type to services args seems fine.

I’ve removed the condition.
Dataproc can take the services argument as None.
Thanks!

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.