Try why3: fix wrong js file

src/trywhy3/index.html

@@ -96,7 +96,7 @@
     </div>
     <script defer="true" src="ace-builds/src-noconflict/ace.js" type="text/javascript" charset="utf-8"></script>
     <script defer="true" type="text/javascript" src="editor_helper.js" ></script>
-    <script defer="true" type="text/javascript" src="try.js" ></script>
+    <script defer="true" type="text/javascript" src="trywhy3.js" ></script>
   </body>
 
 </html>