Support starting sidekiq-cluster for all queues for one or multiple processes (using queue-selector)

Currently sidekiq-cluster supports hacky ways of starting one or multiple processes handling all available queues (such as ee/bin/sidekiq-cluster -n '' ''). Ideally we need a clean way of starting a cluster fetching all available queues so we can use it both at GDK and Omnibus gitlab.rb file.

Proposal

Introduce a name=* for the --experimental-queue-selector syntax that would catch all available queues. Starting multiple processes would be a matter of repeating the query, as we currently do for queue groups:

--experimental-queue-selector 'name=*' 'name=*'

Old description.

From gitlab-org/gitlab#34396 (closed)

Find a way to consolidate queue configuration between 1P and nP setups, since they use vastly different approaches currently.

This might require not only changes in GitLab Rails, but also in omnibus to ensure backwards compatibility for users who have configured sidekiq in a certain way.