Import currently forces Basis Universal which is buggy in Godot 4.0 and 4.1

[lyuma]

There's a Godot bug in which the basis universal code looks up in source_images by the texture index, which is wrong. This will be incorrect or crash Godot if textures and images are not one-to-one in the GLTF document.

Currently the only workaround is to disable embedding which dumps all the textures into the project.

(Furthermore, for a game that loads VRM at runtime, they might not be able to afford compressing to basis during load)