Disable retries for remote mirror update worker

By default, Sidekiq will retry 25 times with an exponential backoff.
This may result in jobs retrying for up to 21 days. That could lead
to an ever-increasing queue size for the remote mirror updates. The
mirrors will attempt to update again within an interval, which should
be sufficient.

app/workers/repository_update_mirror_worker.rb

@@ -4,7 +4,8 @@ class RepositoryUpdateMirrorWorker
   include Sidekiq::Worker
   include Gitlab::ShellAdapter
 
-  sidekiq_options queue: :gitlab_shell
+  # Retry not neccessary. It will try again at the next update interval.
+  sidekiq_options queue: :gitlab_shell, retry: false
 
   attr_accessor :project, :repository, :current_user
 

changelogs/unreleased-ee/sidekiq_set_retries.yml

+---
+title: Disable retries for remote mirror update worker
+merge_request: 848
+author: