ci/windows: Install Graphics-Tools package on the test image

This package contains the D3D12 debug layer. I was able to use this to get more info for a CI failure that I was only seeing on the server but not locally - but right now it requires manually dumping debug messages from the ID3D12InfoQueue to stdout or stderr, and I haven't figured out a great way to integrate that all-up into the d3d12 driver or Dozen, I had just hacked it in. But since this requires a container rebuild I figured I'd get this in sooner and figure that part out later.