REFACTOR: Move queue_jobs out of SiteSetting

It is not a setting, and only relevant in specs. The new API is:

```
Jobs.run_later!        # jobs will be thrown on the queue
Jobs.run_immediately!  # jobs will run right away, avoid the queue
```

config/environments/test.rb

@@ -63,14 +63,12 @@ Discourse::Application.configure do
       s.set_regardless_of_locale(:crawl_images, false)
       s.set_regardless_of_locale(:download_remote_images_to_local, false)
       s.set_regardless_of_locale(:unique_posts_mins, 0)
-      # Running jobs are expensive and most of our tests are not concern with
-      # code that runs inside jobs
-      s.set_regardless_of_locale(:queue_jobs, true)
       # disable plugins
       if ENV['LOAD_PLUGINS'] == '1'
         s.set_regardless_of_locale(:discourse_narrative_bot_enabled, false)
       end
     end
+
     SiteSetting.refresh!
   end
 end