Fix DescriptorSetLayout Hash to look at VkSamplerCreateInfo

[spencer-lunarg]

(possibility duplicate of #10098) and internal spec tracker at https://gitlab.khronos.org/vulkan/vulkan/-/issues/4415

The core issue is if you go

VkSamplerCreateInfo ci;
vkCreateSample(ci, &sampler_0);
vkCreateSample(ci, &sampler_1);

vkCreatePipelineLayout(pImmutableSamplers = sampler_0, &pipe_layout_0);
vkCreatePipelineLayout(pImmutableSamplers = sampler_1, &pipe_layout_1);

vkCmdBindPipeline(pipeline); // layout_0
vkCmdBindDescriptorSets(pipe_layout_1);
vkCmdDraw();

you will hit VUID-vkCmdDraw-None-08600 but that is wrong

The reason for this is because the vvl::DescriptorSetLayoutDef::hash() doesn't account for the contents of pImmutableSamplers. For 2 VkSampler to be "identically defined" (Compatible) the VkSamplerCreateInfo must match

I have some tests (--gtest_filter=*ImmutableSamplerIdenticallyDefined*) that can be used to test the expected output (https://github.com/KhronosGroup/Vulkan-ValidationLayers/pull/10548/files)

We have a CompareSamplerCreateInfo that can be made use