Fix WASM import error

wasm/demo/src/index.js

@@ -1,6 +1,6 @@
 import './style.css';
 import 'codemirror/lib/codemirror.css';
-import 'xterm/dist/xterm.css';
+import 'xterm/lib/xterm.css';
 
 // A dependency graph that contains any wasm must all be imported
 // asynchronously. This `index.js` file does the single async import, so