Add tests for Space classes

ci/generate_test_data.sh

nifty/spaces/hp_space/hp_space.py

test/common.py

test/data/gen_gl_space_data.py

test/data/gen_hp_space_data.py

test/data/gl_space.npz

test/data/hp_space.npz

test/test_nifty.py

test/test_spaces/test_gl_space.py

test/test_spaces/test_hp_space.py

test/test_spaces/test_interface.py

test/test_spaces/test_lm_space.py

test/test_spaces/test_rg_space.py