Link image_copy depth/stencil dx12 failures to #8133 (#8148)

Author: andyleiserson

cts_runner/test.lst

@@ -73,6 +73,7 @@ webgpu:api,validation,encoding,queries,general:occlusion_query,query_index:*
 webgpu:shader,validation,extension,dual_source_blending:blend_src_syntax_validation:*
 webgpu:api,validation,image_copy,buffer_texture_copies:depth_stencil_format,copy_usage_and_aspect:*
 webgpu:api,validation,image_copy,buffer_texture_copies:depth_stencil_format,copy_buffer_size:*
+// image_copy depth/stencil failures on dx12: https://github.com/gfx-rs/wgpu/issues/8133
 fails-if(dx12) webgpu:api,validation,image_copy,buffer_texture_copies:depth_stencil_format,copy_buffer_offset:format="depth32float";aspect="depth-only";copyType="CopyT2B"
 fails-if(dx12) webgpu:api,validation,image_copy,buffer_texture_copies:depth_stencil_format,copy_buffer_offset:format="depth24plus-stencil8";aspect="stencil-only";copyType="CopyB2T"
 fails-if(dx12) webgpu:api,validation,image_copy,buffer_texture_copies:depth_stencil_format,copy_buffer_offset:format="depth24plus-stencil8";aspect="stencil-only";copyType="CopyT2B"