Use ES Module Export in wrapAssembly.js

Summary: This is needed to make Webpack happy when bundling Yoga. Webpack assumes this is an ESModule after following it from the package.json export map. We are already importing this via default import.

Reviewed By: GijsWeterings

Differential Revision: D46811190

fbshipit-source-id: 7a074e5d2aa9c0cb4b59e506a0d910762a62dd58

javascript/src/wrapAssembly.js

@@ -9,7 +9,7 @@
 
 import YGEnums, {Unit, Direction} from './generated/YGEnums';
 
-module.exports = lib => {
+export default function wrapAssembly(lib) {
   function patch(prototype, name, fn) {
     const original = prototype[name];
 
@@ -143,4 +143,4 @@ module.exports = lib => {
     Node: lib.Node,
     ...YGEnums,
   };
-};
+}