Minor fixes on extra_sidekiq_routing.md

doc/administration/operations/extra_sidekiq_routing.md

@@ -99,7 +99,7 @@ based on a subset of worker attributes:
 - `urgency` - how important it is that this queue's jobs run
   quickly. Can be `high`, `low`, or `throttled`. For example, the
   `authorized_projects` queue is used to refresh user permissions, and
-  is high urgency.
+  is `high` urgency.
 - `worker_name` - the worker name. The other attributes are typically more useful as
   they are more general, but this is available in case a particular worker needs
   to be selected.