graphics/vulkan-headers: update to 1.3.246

Force rebuild vulkan-loader to make sure vulkaninfo shows the new version.

Changes: https://github.com/KhronosGroup/Vulkan-Headers/compare/v1.3.245...v1.3.246
Reported by: Repology, portscout

(cherry picked from commit 9ee0e4b037ee7cd5ea8d213db9e566ebef2fbe2c)