Editorial: Align with Web IDL specification

Author: autokagami

index.html

@@ -3889,7 +3889,7 @@ <h2>The <dfn>ThingDiscoveryProcess</dfn> interface</h2>
         readonly attribute boolean done;
         readonly attribute Error? error;
         undefined stop();
-        async iterable&lt;ThingDescription&gt;;
+        async_iterable&lt;ThingDescription&gt;;
       };
     </pre>
     <p>