This reverts commit 677271a3.
"Unbreak recovery test on Windows"

The test hangs on Windows, and attempts to remedy the problem have
proved fragile at best. So we simply disable the test on Windows perl.
(Msys perl seems perfectly happy).

Discussion: https://postgr.es/m/5b748470-7335-5439-e876-6a88c951e1c5@dunslane.net