fix a bug related to track key/label

tripal_jbrowse_mgmt/includes/tripal_jbrowse_mgmt_tracks.form.inc

@@ -486,7 +486,7 @@ function tripal_jbrowse_mgmt_json_editor_advance_form_submit($form, &$form_state
 
   $json = $form_state['track_json'];
   $json['tracks'][$track_index] = json_decode($track_all_config, TRUE);
-  tripal_jbrowse_mgmt_update_track($track, ['label' => $json['tracks'][$track_index]['label']]);
+  tripal_jbrowse_mgmt_update_track($track, ['label' => $json['tracks'][$track_index]['key']]);
 
   if (tripal_jbrowse_mgmt_save_json($track->instance, $json) === FALSE) {
     drupal_set_message(