Backport of 'Move ConcurrencyLimit::ResumeWorker cron config to CE'

What does this MR do and why?

Backports !225235 (merged) — moves ConcurrencyLimit::ResumeWorker cron config from EE to CE.

Problem: The cron job is only registered for EE, but the concurrency limit middleware is a CE middleware. Deferred jobs stall indefinitely in the concurrency limit queue on CE instances.

Solution: Register the cron config in CE so it applies regardless of edition.

Backport notes for 18.7: Conflict in config/initializers/1_settings.rb resolved by taking only the concurrency_limit_resume_worker CE registration (dropping the topology_service_stale_requests_cleanup_worker lines that exist in master/18.9 but not in 18.7). The EE-block removal of concurrency_limit_resume_worker applied cleanly.

Related:

• Original MR: !225235 (merged)
• Issue: #591124 (closed)

MR acceptance checklist

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• This MR is backporting a bug fix, documentation update, or spec fix, previously merged in the default branch.
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• Ensure the e2e:test-on-omnibus-ee job has succeeded, or if it has failed, investigate the failures. If you determine the failures are unrelated, you may proceed. If you need assistance investigating, reach out to a Software Engineer in Test in #s_developer_experience.

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