Summary:
Since moving Switch to a function component it is no longer possible to get the native switch ref. This adds forwardRef so it is possible again.
## Changelog
[General] [Fixed] - Fix Switch ref forwarding
Pull Request resolved: https://github.com/facebook/react-native/pull/31629
Test Plan: Tested the change in an app using react-native-gesture-handler, which tries to set a ref on Switch. Also made sure flow still passes.
Reviewed By: TheSavior
Differential Revision: D28839605
Pulled By: lunaleaps
fbshipit-source-id: 1fee86145caeabb60c0010bb9062dddca419f7ca