Fix a link

Signed-off-by: Taylor Smock <taylor.smock@kaart.com>

public/index.html

@@ -15,6 +15,6 @@
   <a href="https://josm.openstreetmap.de/wiki/Help/Plugin/MapWithAI">MapWithAI Plugin Help</a>
 </div>
 <div class=mapwithaisourcetable>
-  <h1><a href="sources.json">Sources</a></h1>
+  <h1><a href="json/sources.json">Sources</a></h1>
 </div>
 </body>