[BUG] Atlas meshes fail to load with brainglobe-atlasapi>=3.0.0 #460

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Atlas meshes can no longer be loaded following the changes in brainglobe-atlasap==3.0.0rc0 as meshes are no longer stored on disk as .obj files. brainrender accesses these files directly to load meshes into vedo.

Expected behaviour
Atlas meshes should be loaded correctly without errors.