Caused by 617858e453.
These formats should use types aligned to 4 bytes. That's generally
required by modern GPUs. Uploading with these types also avoids
automatic conversion by the Vulkan backend which is something
we're hoping to remove fully.
In the end this PR removes a bunch of code related to supporting
the older single-byte formats.
Pull Request: https://projects.blender.org/blender/blender/pulls/138836