Make glslc program really required when Vulkan is used
The REQUIRED keyword has to be uppercase to stop the cmake step if glslc is not found.
GitLab upgrade completed. Current version is 18.6.4
https://about.gitlab.com/releases/2025/11/20/gitlab-18-6-released/
The REQUIRED keyword has to be uppercase to stop the cmake step if glslc is not found.