fix: add ImageSource type to TypeScript (#51969)

Summary: This PR adds ImageSource type to ImageSource.d.ts which is defined in Flow: https://github.com/facebook/react-native/blob/d6f29c8afd14b2cc835649db3c59ed2f0e685331/packages/react-native/Libraries/Image/ImageSource.js#L87-L90 But not in the TypeScript file. ## Changelog: [GENERAL] [FIXED] - add ImageSource type to TypeScript Pull Request resolved: #51969 Test Plan: CI Green Reviewed By: fabriziocucci Differential Revision: D76532377 Pulled By: Abbondanzo fbshipit-source-id: f1bbcd3b3fc07bb0f7e82f81ebaffedf9bc06148

Author: okwasniewski

packages/react-native/Libraries/Image/ImageSource.d.ts

@@ -72,3 +72,8 @@ export interface ImageURISource {
 }
 
 export type ImageRequireSource = number;
+
+export type ImageSource =
+ | ImageRequireSource
+ | ImageURISource
+ | ReadonlyArray<ImageURISource>;