Function format_vulkan 

pub fn format_vulkan(
    version: &str,
    driver_name: &str,
    driver_info: &str,
) -> String

Render the Vulkan field from its parts.

driver_name/driver_info are empty when the driver did not fill the VkPhysicalDeviceDriverProperties chain, which happens on any instance created below Vulkan 1.2 — silently, with no error. The version alone is still worth printing.