Sidekiq: enable queue negation, akin to sidekiq-cluster

Summary

Omnibus GitLab has the ability to make use of sidekiq-cluster which is included in the Rails codebase under ee/bin/sidekiq-cluster. This functionality includes the --negate option, which allows one to start extra Sidekiq processes using the default queue list (sidekiq_queues.yml) minus the list provided.

These provide the ability to configure the entirety of sidekiq_queues.yml, on a per Pod basis. While this provides great flexibility, it does not provide the simplicity of negation.

We should provide a simple means of using negation logic

Configuration proposed

gitlab:
  sidekiq:
    pods:
    - name: no-pages
      queues:
      # consume all default queues, _except_ `pages`
      negateQueues:
      - pages

Current behavior

Removing a single queue currently requires copying all of sidekiq_queues.yml into a pods: [] entry.

Expected behavior

Disabling single queues is as simple as negateQueues: [ x, y]

Versions

• Chart: a1751ec1