Fix wrong type hints for Tensor.is_cuda, is_leaf (#21192)
Summary:
`Tensor.is_cuda` and `is_leaf` is not a predicate function but a `bool` attribute. This patch fixes the type hints in `torch/__init__.pyi` for those attributes.
```diff
- def is_cuda(self) -> bool: ...
+ is_cuda: bool
- def is_leaf(self) -> bool: ...
+ is_leaf: bool
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/21192
Differential Revision: D15592766
Pulled By: soumith
fbshipit-source-id: 8c4ecd6939df8b8a8a19e1c9db6d40193bca7e4a
