SDL3/CategoryGPU: SDL_shadercross wiki page doesn't exist yet, can cr…

…eate a wiki page link later when it exists.

Live page is here: https://wiki.libsdl.org/SDL3/CategoryGPU

SDL3/CategoryGPU.md

@@ -115,7 +115,7 @@ explaining this situation.
 
 It is optimal for apps to pre-compile the shader formats they might use,
 but for ease of use SDL provides a separate project,
-[[SDL_shadercross](SDL_shadercross)](https://github.com/libsdl-org/SDL_shadercross)
+[SDL_shadercross](https://github.com/libsdl-org/SDL_shadercross)
 , for performing runtime shader cross-compilation. It also has a CLI
 interface for offline precompilation as well.