Remove obsolete setting of Zeitwerk

It's the default now.
https://guides.rubyonrails.org/upgrading_ruby_on_rails.html#the-setter-config-autoloader-has-been-deleted

config/application.rb

@@ -249,7 +249,5 @@ module Openfoodnetwork
     config.active_storage.variable_content_types += ["image/svg+xml"]
 
     config.exceptions_app = self.routes
-
-    config.autoloader = :zeitwerk
   end
 end