tests/test_nanshe_registerer.py: Label all 3D tests with an attribute.
tests/test_nanshe_registerer.py: Label all 3D tests with an attribute.

DudLab/nanshe,jakirkham/nanshe,nanshe-org/nanshe,jakirkham/nanshe,nanshe-org/nanshe,DudLab/nanshe