Fix backward compatibility check test for schemas containing (#34782)
Summary:
"torch.classes".
BC check tests skips adding torch.classes based schemas to existing
schemas. Removed the skip.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34782
Test Plan:
cd test/backward_compatibility
python dump_all_function_schemas.py --filename new_schemas.txt
python check_backward_compatibility.py --new-schemas new_schemas.txt
Before this PR fails with:
```
Mar 15 11:12:20 Broken ops: [
Mar 15 11:12:20 _xnnpack::conv2d_packed(Tensor X, __torch__.torch.classes.XNNPackConv2dOpContext W_prepack) -> (Tensor Y)
Mar 15 11:12:20 _xnnpack::conv2d_prepack(Tensor W, Tensor? B, int[2] stride, int[2] padding, int[2] dilation, int groups) -> (__torch__.torch.classes.XNNPackConv2dOpContext)
Mar 15 11:12:20 _xnnpack::linear_packed(Tensor X, __torch__.torch.classes.XNNPackLinearOpContext W_prepack) -> (Tensor Y)
Mar 15 11:12:20 _xnnpack::linear_prepack(Tensor W, Tensor? B=None) -> (__torch__.torch.classes.XNNPackLinearOpContext)
Mar 15 11:12:20 ]
```
After this PR, it passes.
Reviewed By: houseroad
Differential Revision: D20461994
Pulled By: kimishpatel
fbshipit-source-id: de692644ee7d49accf2d8260cd3a10f6e147653a
