Eager load a project's route and its namespace with route in project_reference_filter

lib/banzai/filter/project_reference_filter.rb

@@ -70,7 +70,7 @@ module Banzai
       # The keys of this Hash are the project paths, the values the
       # corresponding Project objects.
       def projects_hash
-        @projects ||= Project.eager_load(:namespace, :route)
+        @projects ||= Project.eager_load(:route, namespace: [:route])
                              .where_full_path_in(projects)
                              .index_by(&:full_path)
                              .transform_keys(&:downcase)