Draft: Bump sidekiq concurrency setting for cng kind deployments

What does this MR do and why?

We currently don't have any monitoring in to cng environment, but anecdotal evidence point to some flakiness in tests that heavily rely on background job processing. Given each job runs 4 parallel test processes, it's crucial for background jobs not to get stuck in the queue. This doubles amount of sidekiq pods (documented replicas setting doesn't seem to work) increases concurrency amount by 50% to ensure background job throughput.

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