Bug 38201: Fix preservation route

This is not correct, we need to retrieve the first parent with
is_end_node==true (I think)

(cherry picked from commit 98fbdf3d6ee7fde3266d52ffa5f46ed9c2320be1)
Signed-off-by: Michaela Sieber <michaela.sieber@kit.edu>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Lucas Gass <lucas@bywatersolutions.com>

koha-tmpl/intranet-tmpl/prog/js/vue/routes/preservation.js

@@ -49,6 +49,7 @@ export const routes = [
                         path: ":train_id",
                         title: $__("Show train"),
                         is_end_node: true,
+                        resource: "Preservation/TrainResource.vue",
                         children: [
                             {
                                 path: "",