Migrate umd examples away from deprecated parcel-bundler dep

Author: tanem

examples/umd-dev/package.json

@@ -6,12 +6,10 @@
   ],
   "version": "0.1.0",
   "private": true,
-  "main": "index.html",
   "scripts": {
-    "start": "parcel index.html --open",
-    "build": "parcel build index.html"
+    "start": "npx serve . --single --listen 1234"
   },
   "devDependencies": {
-    "parcel-bundler": "1.12.5"
+    "serve": "^14.2.0"
   }
 }

examples/umd-prod/package.json

@@ -6,12 +6,10 @@
   ],
   "version": "0.1.0",
   "private": true,
-  "main": "index.html",
   "scripts": {
-    "start": "parcel index.html --open",
-    "build": "parcel build index.html"
+    "start": "npx serve . --single --listen 1235"
   },
   "devDependencies": {
-    "parcel-bundler": "1.12.5"
+    "serve": "^14.2.0"
   }
 }