enable gadm for base map after fetch request

seshat/apps/core/templates/core/polity_map.html

@@ -303,9 +303,7 @@ <h2>How to use Seshat Maps</h2>
                             };
                         });
 
-                        // Enable the radio selection after the fetch request is done
-                        document.getElementById('baseMapCurrentLoadingIndicator').style.display = 'none';
-                        document.getElementById('baseMapCurrent').disabled = false;
+                        document.getElementById('baseMap').options[4].disabled = false;
                     });
             });