Enable the DepthStencilTest.* that was failing before.

Bug: angleproject:6094
Change-Id: I8c69de4927c0e70143cd632e97f0abdb740a013f
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2982550
Commit-Queue: Gert Wollny <gert.wollny@collabora.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Cody Northrop <cnorthrop@google.com>