Revert "Merge branch 'pipeline-editor/linked-pipelines' into 'master'"

What does this MR do and why?

Reverts !72255 (merged)

Fixes master:foss-broken #343701 (closed) . It seems safe to revert this MR as (according to the MR description !72255 (merged) ) it was for a feature that is not enabled yet so we there should be no user impact.

This can give the team time to fix the problem in a new MR with pipeline:run-as-if-foss label to ensure the tests are passing properly.

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