Test shader group handle alignment

Test shader group handle alignment

This commit adds a new test group that verifies the advertised supported
shader group handle alignment in shader binding tables works as
expected.

The new tests create shader binding tables with shader record buffers
that act as padding bytes to achieve the desired alignments. These
shader record buffers are also read from ray tracing shaders and
verified to have the right contents.

New tests:
dEQP-VK.ray_tracing_pipeline.shader_binding_table.handle_alignment.*

Components: Vulkan
VK-GL-CTS issue: 3298

Change-Id: Id2d4f11ed2fcf56ce30e1a5896d38416cbaf1b82