Summary:
Enhancing native iOS modules and preventing crashes inside the RCTAlertController
## Changelog
[iOS][Fixed] - Handle properly a `nil` `keyWindows` in the AlertController
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Pull Request resolved: https://github.com/facebook/react-native/pull/35689
Reviewed By: cipolleschi
Differential Revision: D42179169
Pulled By: ryancat
fbshipit-source-id: 05a6788f610db1d222e3c10b3c774c75edaf55f5