Export EmitterSubscription TypeScript Type (#36632)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/36632

Discovered when bumping the RN documentation to typecheck against 0.72, https://github.com/facebook/react-native/pull/36109 removed the `EmitterSubscription` type which should be kept public.

Changelog:
[General][Fixed] -  Export EmitterSubscription TypeScript Type

Reviewed By: cortinico

Differential Revision: D44375081

fbshipit-source-id: c8dbd5694d3a728a0a2091210894d27c9d84a012

packages/react-native/types/__typetests__/index.tsx

@@ -40,6 +40,8 @@ import {
   DrawerLayoutAndroid,
   DrawerSlideEvent,
   DynamicColorIOS,
+  EmitterSubscription,
+  EventSubscription,
   FlatList,
   FlatListProps,
   GestureResponderEvent,

packages/react-native/types/index.d.ts

@@ -147,6 +147,10 @@ export * from '../Libraries/Utilities/Platform';
 export * from '../Libraries/Vibration/Vibration';
 export * from '../Libraries/YellowBox/YellowBoxDeprecated';
 export * from '../Libraries/vendor/core/ErrorUtils';
+export {
+  EmitterSubscription,
+  EventSubscription,
+} from '../Libraries/vendor/emitter/EventEmitter';
 
 export * from './public/DeprecatedPropertiesAlias';
 export * from './public/Insets';