Fix call to hoomd.dump.GSD in test_dump in teest_gsd.py
Fix call to hoomd.dump.GSD in test_dump in teest_gsd.py

joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue