chore: use npx to run react-native (#32788)

Summary:
the docs mostly use npx to run react native (https://reactnative.dev/docs/environment-setup) and I do not have react native installed globally, so I think npx should be used here as well

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[General] [changed] - improved bug template

Pull Request resolved: https://github.com/facebook/react-native/pull/32788

Test Plan: not needed

Reviewed By: lunaleaps

Differential Revision: D33235384

Pulled By: cortinico

fbshipit-source-id: e8d50bb6172066da8d656d3efd0cb6cd17ab1487