Fix unstable regression test results.

Fix unstable regression test results.

Commit 2ac3ef7a0 added a query with an underdetermined output row order;
it has failed multiple times in the buildfarm since then.  Add an ORDER BY
to fix.  Also, don't rely on a DROP CASCADE to drop in a well-determined
order; that hasn't failed yet but I don't trust it much, and we're not
saving any typing by using CASCADE anyway.