Revert "Merge branch 'jennli-switch-off-sidekiq' into 'master'"

What does this MR do and why?

Revert "Merge branch 'jennli-switch-off-sidekiq' into 'master'"

This reverts merge request !152437 (merged) because #460842 (closed) was resolved by setting FF_NETWORK_PER_BUILD: true as a CI/CD variable in gitlab-org/gitlab.

Related to #460842 (comment 1898564226)

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