Enable and remove the FF ci_batch_project_includes_context

What does this MR do and why?

This MR removes the FF ci_batch_project_includes_context

It is already enabled on GitLab SaaS.

• Rollout issue: #392746 (closed)
• Main issue: #382751 (closed)
• Introduced in: !112570 (merged)
• Fixed in: !118670 (merged)

MR acceptance checklist

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