Format vulkan_and_spirv.md, to fix bullet point styling.
Format vulkan_and_spirv.md, to fix bullet point styling.

PiperOrigin-RevId: 293480290

iree-org/iree,iree-org/iree,google/iree,iree-org/iree,iree-org/iree,google/iree,google/iree,iree-org/iree,google/iree,google/iree,iree-org/iree,iree-org/iree,google/iree,google/iree