tensor_numpy: add missing include header (#24042)
Summary:
This patch fixes the following error:
```
In file included from /path/to/lib/python3.6/site-packages/numpy/core/include/numpy/arrayobject.h:4:0,
from ../torch/csrc/utils/numpy_stub.h:19,
from ../torch/csrc/utils/tensor_numpy.cpp:2:
../torch/csrc/utils/tensor_numpy.cpp: In function 'bool torch::utils::is_numpy_scalar(PyObject*)':
../torch/csrc/utils/tensor_numpy.cpp:223:11: error: 'PyInt_Check' was not declared in this scope
return (PyArray_IsIntegerScalar(obj) ||
^
../torch/csrc/utils/tensor_numpy.cpp:225:1: warning: control reaches end of non-void function [-Wreturn-type]
}
^```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/24042
Differential Revision: D16732545
Pulled By: ezyang
fbshipit-source-id: 8d73d228b88b4a95daedcd7a4ef81c268830792e
