Simplify demo

Author: marijnh

demo/demo.ts

@@ -7,5 +7,5 @@ import {javascript} from "@codemirror/lang-javascript"
     basicSetup,
     javascript(),
   ],
-  parent: document.querySelector("#editor")!
+  parent: document.body
 })

demo/index.html

@@ -9,6 +9,5 @@
 </style>
 
 <h1>CM6</h1>
-<div id=editor></div>
 
 <script type=module src="_m/demo.js"></script>