* Shader -> SPIR-V at CTS build time (#1849)
Instead of relying on prebuilt checked-in SPIR-V files, compile
available shaders at CTS build time.
* Add dependency on glslc (available as part of VULKAN_SDK).
* Add optional build flag BUILD_GLSL_SHADERS, OFF by default.
* Remove pre-built SPIR-V files
* Compile Shader -> SPIR-V at CTS build time
* Use glslangValidator for shader -> spirv
* Add glslangValidator tool for shader -> spirv
* Refactor glslangValidator tool retrieval
* Address review comments
* Use add_subdirectory() instead of include()
* Use glslang instead of glslangValidator
* Update Github actions CI to install Vulkan SDK
7f1caf4aa9