tests: Rename scissor/vp count test and fix errors
tests: Rename scissor/vp count test and fix errors

Renamed test to add additional validatin checks, fixed an
unexpected error in test.

Change-Id: I013102f716795713ea2597cd5e54a79346eada29

KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers