Summary:
This diff updates the flow types for the ActivityIndicator size prop.
The android component [here](diffusion/FBS/browse/master/xplat/js/react-native-github/ReactAndroid/src/main/java/com/facebook/react/views/progressbar/ReactProgressBarViewManager.java$31-30) does not use a size prop
The iOS component [here](diffusion/FBS/browse/master/xplat/js/react-native-github/React/Fabric/Mounting/ComponentViews/ActivityIndicator/RCTActivityIndicatorViewComponentView.mm;e82762cefe5cddad4a7e8144c42c76eb4d907e56$14-15,23) uses the size prop, but only for small/large, not for the number type
Reviewed By: TheSavior
Differential Revision: D14247432
fbshipit-source-id: 43b74574548eaf97f96d68c18ed627465fd5e133