Require ActionCable and ActiveJob to workaround a bug

Even if these aren't being used, it turns out that turbo-rails still
tries to autoload them in production. See:

  * hotwired/turbo-rails#478
  * hotwired/turbo-rails#512

There's a workaround for the ActionCable issue but not for the
ActiveJob one, so we just relent and require them.

config/application.rb

@@ -3,15 +3,15 @@
 require "rails"
 # Pick the frameworks you want:
 require "active_model/railtie"
-# require "active_job/railtie"
+require "active_job/railtie"
 # require "active_record/railtie"
 # require "active_storage/engine"
 require "action_controller/railtie"
 # require "action_mailer/railtie"
 # require "action_mailbox/engine"
 # require "action_text/engine"
 require "action_view/railtie"
-# require "action_cable/engine"
+require "action_cable/engine"
 # require "rails/test_unit/railtie"
 
 # Require the gems listed in Gemfile, including any gems