‘functorch’ not needed in requirements.txt?

As it says on https://pytorch.org/functorch/stable/:

> We’ve integrated functorch into PyTorch. As the final step of the integration, the functorch APIs are deprecated as of PyTorch 2.0. Please use the torch.func APIs instead and see the [migration guide](https://pytorch.org/docs/master/func.migrating.html) and [docs](https://pytorch.org/docs/master/func.html) for more details.