Revert "Temporarily stop running tests on D3D12 with use_tint_generator"

This reverts commit 5c9b6a8f81abf54f1b8ba1c6d54c4037ecadba52.

The issue has now been fixed in Tint and rolled into Dawn.

Fixed: dawn:758
Change-Id: Id7deb6cea9f22ee8c5f345a28d2d37499b47d692
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/48080
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Auto-Submit: James Price <jrprice@google.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/tests/DawnTest.cpp b/src/tests/DawnTest.cpp
index f35687e..26bc121 100644
--- a/src/tests/DawnTest.cpp
+++ b/src/tests/DawnTest.cpp
@@ -522,6 +522,7 @@
                 // test skips on all backends, we can remove this and use a test suite with
                 // use_tint_generator in the command line args instead.
                 if (params[i].backendType == wgpu::BackendType::Vulkan ||
+                    params[i].backendType == wgpu::BackendType::D3D12 ||
                     params[i].backendType == wgpu::BackendType::OpenGL ||
                     params[i].backendType == wgpu::BackendType::OpenGLES) {
                     BackendTestConfig configWithTint = params[i];