Summary:
Just thought I'd add these instructions so devs don't have to check the docs. Also, it makes iOS match Android with instructions in the configuration files
## Changelog
N/A (in my opinion)
Pull Request resolved: https://github.com/facebook/react-native/pull/30461
Test Plan: N/A (because not a code change)
Reviewed By: hramos
Differential Revision: D25309687
Pulled By: TheSavior
fbshipit-source-id: a1907089b9d2e7fe6f2498ce27129c3ae65f7c9a