layers:Remove redundant periods
layers:Remove redundant periods

These error messages are all amended to error messages that already
include a period at the end so deleting the extra periods.

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