Backport "Move unlock pipeline cron scheduler out of ee" to 16.6

What does this MR do and why?

This backports !137749 (merged) to 16.6.

The bug was introduced in 16.5 when we introduced the new mechanism for unlocking pipelines. Unfortunately, the cron scheduler was unintentionally scoped to only run for Gitlab.ee? which resulted to non-ee instances to have their pipelines never get unlocked, and job artifacts to never be deleted.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• This MR is backporting a bug fix, documentation update, or spec fix, previously merged in the default branch.
• The MR that fixed the bug on the default branch has been deployed to GitLab.com (not applicable for documentation or spec changes).
• This MR has a severity label assigned (if applicable).
• This MR has been approved by a maintainer (only one approval is required).
• Ensure the e2e:package-and-test-ee job has either succeeded or been approved by a Software Engineer in Test.

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