Revert "Fix parallel-safety check of expressions and predicate for index builds"
This reverts commit
eae7be600be7, following a discussion with Tom Lane,
due to concerns that this impacts the decisions made by the planner for
the number of workers spawned based on the inlining and const-folding of
index expressions and predicate for cases that would have worked until
this commit.
Discussion: https://postgr.es/m/162802.
1709746091@sss.pgh.pa.us
Backpatch-through: 12