This PR adds a new command line argument to validate all statically
defined shaders. It is useful for platform support to understand
what isn't working.
It only checks statically defined shaders. Dynamic shaders (EEVEE/Compositor)
can still be fail.
The report is printed to console. After checking with windows platform and
triaging we could also add it to gpu debug script. There is a risk of adding it there
as it might crash and don't store any output.
Pull Request: https://projects.blender.org/blender/blender/pulls/117326