Make sidekiq-cluster play well with Sidekiq 5.2.2+
Sidekiq 5.2.2 introduced a change (https://github.com/mperham/sidekiq/pull/3936/files) that prevents queue names from being duplicated. This breaks our current GitLab.com config because we have some sidekiq-cluster processes configured as the following:
sidekiq_cluster['queue_groups'] = ["process_commit,process_commit,process_commit"]To keep things backwards compatible, we now only pass unique queue names but scale the weights accordingly by the number of queues mentioned.