Update doc because emscripten toolchain file was removed.

Working-for-Web-(HTML5).md

@@ -88,14 +88,6 @@ One note here - if you're using **vcpkg** for package management and have instal
 cmake -H . -B build -G Ninja "-DVCPKG_CHAINLOAD_TOOLCHAIN_FILE=<fullpath_to_emsdk>/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake" "-DCMAKE_TOOLCHAIN_FILE=<path_to_vcpkg>/scripts/buildsystems/vcpkg.cmake" "-DVCPKG_TARGET_TRIPLET=wasm32-emscripten"
 ```
 
-**The third option** is to use the lighter but included toolchain in raylib:
-
-```
-cmake -H . -B build -DPLATFORM=Web -G Ninja -DCMAKE_TOOLCHAIN_FILE=cmake/emscripten.cmake
-```
-_(The "-H ." is deprecated since CMake 3.13 and if you are using higher version please replace the argument with "-S .")_
-_(The ninja generator is optional and you can use your system default by removing "-G Ninja".)_
-
 ##### Building with CMake
 
 To build the project you would need to execute: