fix link to 4.1.x

Author: giohappy

index.html

@@ -30,7 +30,7 @@ <h4 class="demo-btn maint"><a href="https://stable.demo.geonode.org">Latest stab
         </div>
         <div class="col-md-4">
           <h4 class="demo-btn stable"><a href="https://development.demo.geonode.org">Development</a></h4>
-          <span><a href="https://github.com/GeoNode/geonode/releases/tag/4.1.x" target="_blank">4.1.x</a></span>
+          <span><a href="https://github.com/GeoNode/geonode/tree/4.1.x" target="_blank">4.1.x</a></span>
         </div>
         <div class="col-md-4">
           <h4 class="demo-btn dev"><a href="https://master.demo.geonode.org">Experimental</a></h4>