Fix unit tests.

Author: duburcqa

tests/test_rigid_physics.py

@@ -577,7 +577,7 @@ def test_link_velocity(gs_sim, tol):
 @pytest.mark.parametrize("gs_integrator", [gs.integrator.Euler])
 def test_pendulum_links_acc(gs_sim, tol):
     pendulum = gs_sim.entities[0]
-    g = gs_sim.rigid_solver._gravity.to_numpy()[2]
+    g = gs_sim.rigid_solver._gravity[0][2]
 
     # Make sure that the linear and angular acceleration matches expectation
     theta = np.random.rand()
@@ -1589,7 +1589,7 @@ def test_contact_forces(show_viewer, tol):
     )
     scene.build()
 
-    cube_weight = scene.rigid_solver._gravity.to_numpy()[2] * cube.get_mass()
+    cube_weight = scene.rigid_solver._gravity[0][2] * cube.get_mass()
     motors_dof = np.arange(7)
     fingers_dof = np.arange(7, 9)
     qpos = np.array([-1.0124, 1.5559, 1.3662, -1.6878, -1.5799, 1.7757, 1.4602, 0.04, 0.04])