planify: Fix GtkMediaStream creation

It looks like we still need the proper `GST_PLUGIN_SYSTEM_PATH_1_0`
to not crash this, I have no idea what can explode if this is set
everywhere (we propagate these in gtk4?) but this will be the simple
workaround for now.

The base and the good plugins are the minimum to avoid the crash for me.

pkgs/applications/office/planify/default.nix

@@ -10,6 +10,7 @@
 , evolution-data-server
 , glib
 , glib-networking
+, gst_all_1
 , gtk4
 , gtksourceview5
 , gxml
@@ -49,6 +50,9 @@ stdenv.mkDerivation rec {
     evolution-data-server
     glib
     glib-networking
+    # Needed for GtkMediaStream creation with success.ogg, see #311295.
+    gst_all_1.gst-plugins-base
+    gst_all_1.gst-plugins-good
     gtk4
     gtksourceview5
     gxml