Remove FF ci_fix_order_of_subsequent_jobs

What does this MR do and why?

This MR removes the FF ci_fix_order_of_subsequent_jobs. It's fully enabled on GitLab.com since March 30th.

• Rollout issue: #345587 (closed)
• Bug issue: #341561 (closed)
• Introduced in: !81087 (merged)

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.