modify comment of mish (#38805)

python/paddle/nn/functional/activation.py

@@ -1200,9 +1200,8 @@ def mish(x, name=None):
 
             import paddle
             import paddle.nn.functional as F
-            import numpy as np
 
-            x = paddle.to_tensor(np.array([-5., 0., 5.]))
+            x = paddle.to_tensor([-5., 0., 5.])
             out = F.mish(x) # [-0.03357624, 0., 4.99955208]
     """
     if in_dygraph_mode():

python/paddle/nn/layer/activation.py

@@ -907,9 +907,8 @@ class Mish(Layer):
         .. code-block:: python
 
             import paddle
-            import numpy as np
 
-            x = paddle.to_tensor(np.array([-5., 0., 5.]))
+            x = paddle.to_tensor([-5., 0., 5.])
             m = paddle.nn.Mish()
             out = m(x) # [-0.03357624, 0., 4.99955208]