[cherry-pick][release-2.40.0] Merge pull request #21895: Drops usage of setWindowingStrategyInterna…

[pabloem]

…l in favour of direct use of WindowFn

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[pabloem]

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[pabloem]

r: @kennknowles

[egalpin]

Thanks for the CP! 🚢

[pabloem]

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[pabloem]

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