pgsql: Fix executor prune failure when plan already pruned

Fix executor prune failure when plan already pruned In a multi-layer partitioning setup, if at plan time all the sub-partitions are pruned but the intermediate one remains, the executor later throws a spurious error that there's nothing to prune. That is correct, but there's no reason to throw an

pgsql: Fix executor prune failure when plan already pruned

Fix executor prune failure when plan already pruned In a multi-layer partitioning setup, if at plan time all the sub-partitions are pruned but the intermediate one remains, the executor later throws a spurious error that there's nothing to prune. That is correct, but there's no reason to throw an