Fix (non) alignment of shader group handles as returned in calls to vkGetRayTracing*ShaderGroupHandles*

[arno-lunarg]

It will soon be clarified in the spec that the shader group handles returned in a call to the vkGetRayTracing*ShaderGroupHandles* functions are tightly packed/not aligned.
Corresponding Gitlab merge request: https://gitlab.khronos.org/vulkan/vulkan/-/merge_requests/6490

I think the only thing that needs to be changed in the ray tracing samples are sbt_size computation, it should use handle_size instead of handle_size_aligned, and the following memory copies that compute offsets using handle_size_aligned.

Vulkan-Samples/samples/extensions/ray_tracing_basic/ray_tracing_basic.cpp

Line 471 in 8ba37b4

const uint32_t sbt_size = group_count * handle_size_aligned;

Vulkan-Samples/samples/extensions/ray_tracing_reflection/ray_tracing_reflection.cpp

Line 583 in 8ba37b4

const auto sbt_size = group_count * handle_size_aligned;

Vulkan-Samples/samples/extensions/ray_tracing_extended/ray_tracing_extended.cpp

Line 852 in 8ba37b4

const uint32_t sbt_size = group_count * handle_size_aligned;