fix seed

Signed-off-by: Jinzhe Zeng <jinzhe.zeng@rutgers.edu>

tests/test_force_grad.py

@@ -95,7 +95,7 @@ def get_dataset(self, system_index=0, batch_index=0):
 
     def test_force_grad(self, threshold=1e-3, delta0=1e-6, seed=20):
         result0 = self.model(**get_data(self.origin_batch))
-        np.random.default_rng().seed(seed)
+        np.random.default_rng(seed)
         errors = np.zeros((self.dpdatasystem._natoms, 3))
         for atom_index in range(self.dpdatasystem._natoms):
             for axis_index in range(3):