Use NULL for nick/blurb in GObject params

As they are only used by gstreamer for gst-inspect & other tools.
Projects like Mutter/gtk have completely dropped them as well, so follow
their path

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/3505>

js/ui/searchController.js

@@ -26,7 +26,7 @@ function getTermsForSearchString(searchString) {
 export const SearchController = GObject.registerClass({
     Properties: {
         'search-active': GObject.ParamSpec.boolean(
-            'search-active', 'search-active', 'search-active',
+            'search-active', null, null,
             GObject.ParamFlags.READABLE,
             false),
     },