fix: Replaced deprecated logger.warn with logger.warning

[Sai-Suraj-27]

What does this PR do?

logging.warn and logging.Logger.warn are deprecated in favor of logging.warning and logging.Logger.warning, which are functionally equivalent. (https://docs.python.org/3/library/logging.html#logging.warning)

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• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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Who can review?

@amyeroberts @ArthurZucker

[amyeroberts]

Thanks!