Remove Sidekiq min-concurrency and max-concurrency

After deprecating #2760 (closed), this issue tracks the removal of min-concurrency and max-concurrency options for the sidekiq-cluster CLI.

Removal entry: https://docs.gitlab.com/ee/update/deprecations.html?removal_milestone=17.0#min-concurrency-and-max-concurrency-in-sidekiq-options

• Remove the options in Omnibus
• Remove the options in sidekiq-cluster CLI (Rails app). Has to be removed after Omnibus removal #3422 (comment 1869926606)
• Remove the options in CNG gitlab-org/build/CNG#1935 (closed)