Adding SPIRV-Cross and SPIRV-Reflect

[spencer-lunarg]

From compiler-explorer/compiler-explorer#7056

I wanted to add the logic to pull down and build SPIRV-Cross and SPIRV-Reflect so that it can be used lived

My thought was "we already do a nightly for SPIRV-Tools so I should be able to mostly copy that, but I can't find anything for that. I found an old commit but not sure how I am suppose to help add these 2 tools/compilers

[spencer-lunarg]

Wanted to also mention that there is a Vulkan SDK that provides all of these binaries ready to go if building them is the time constraint