[ONNX] Capture annotated attributes for local function
Enables local function export to capture annotated attributes.
For example:
```python
class M(torch.nn.Module):
num_layers: int
def __init__(self, num_layers):
super().__init__()
self.num_layers = num_layers
def forward(self, args):
...
```
`num_layers` will now be captured as attribute of local function `M`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/72883
