Gracefully recover from Redis connection failures in Sidekiq initializer

* Closes gitlab-org/gitlab-ce#25143
* Closes gitlab-org/omnibus-gitlab#1743

changelogs/unreleased/rescue-from-redis-init-errors.yml

+---
+title: Gracefully recover from Redis connection failures in Sidekiq initializer
+merge_request: 
+author: 

config/initializers/sidekiq.rb

@@ -61,5 +61,5 @@ begin
       end
     end
   end
-rescue Redis::BaseError, SocketError
+rescue Redis::BaseError, SocketError, Errno::ENOENT, Errno::EAFNOSUPPORT, Errno::ECONNRESET, Errno::ECONNREFUSED
 end