Add mailers queue to the background_jobs script.

bin/background_jobs

@@ -37,7 +37,7 @@ start_no_deamonize()
 start_sidekiq()
 {
-  bundle exec sidekiq -q post_receive -q mailer -q archive_repo -q system_hook -q project_web_hook -q gitlab_shell -q incoming_email -q runner -q common -q default -e $RAILS_ENV -P $sidekiq_pidfile $@ >> $sidekiq_logfile 2>&1
+  bundle exec sidekiq -q post_receive -q mailers -q archive_repo -q system_hook -q project_web_hook -q gitlab_shell -q incoming_email -q runner -q common -q default -e $RAILS_ENV -P $sidekiq_pidfile $@ >> $sidekiq_logfile 2>&1
 }
 load_ok()