This PR adds initial cube (array) support. Depending on how the texture
is used a different image view is created. When used as a framebuffer
attachment only a single side of the cubemap is attached. The image
view is attached as a 2d texture array. When used as a shader resource
the image view is a cubemap.
Also adds test cases to test both scenarios.
Pull Request: https://projects.blender.org/blender/blender/pulls/108794