chore: fix develop watch (#2237)

packages/netlify-cms-widget-datetime/package.json

@@ -18,8 +18,7 @@
   ],
   "sideEffects": false,
   "scripts": {
-    "watch": "webpack -w",
-    "develop": "npm run watch",
+    "develop": "yarn build:esm --watch",
     "build": "cross-env NODE_ENV=production webpack",
     "build:esm": "cross-env NODE_ENV=esm babel src --out-dir dist/esm --ignore src/**/__tests__/* --root-mode upward"
   },

packages/netlify-cms-widget-datetime/src/index.js

@@ -9,3 +9,4 @@ const Widget = (opts = {}) => ({
 });
 
 export const NetlifyCmsWidgetDatetime = { Widget, controlComponent, previewComponent };
+export { Widget as default, controlComponent, previewComponent };