Commit 0be2e5b0 added a regression test to check that if a view contains
an ORDER BY, that ORDER BY is obeyed on selecting from the view. However,
it forgot to add the test to the schedule, so it was never run. Add it.

There is actually a problem with the test as it is written: gpdiff masks
out the differences in the row order, so this test won't catch the problem
that it was originally written for. Nevertheless, seems better to enable
the test and run, than not run it at all. But add a comment to point that
out.