[primTorch] Adds broadcast_shapes reference (#78612)
1. Added references `_refs.broadcast_shapes`
2. Added OpInfo test for `torch.broadcast_shapes`
A few minor changes:
- `test_python_ref_meta` and `_ref_test_helper` update to avoid non-tensor outputs
- type annotation update for `_resize_meta`
Pull Request resolved: https://github.com/pytorch/pytorch/pull/78612
Approved by: https://github.com/mruberry
