fix dlrm accuracy test in max-autotune (#122012)
torchrec_dlrm training fail the accuracy check when max-autotune is enabled.
I found there is no real issue in PT2. We fail to get fp64 reference results for the accuracy check. In max-autotune mode numerical may change a bit and cause the cosine similarity check fail. Using fp64 baseline is more reliable and make the test pass.
The reason why we are not using a fp64 baseline earlier is because torchrec uses a dataclass [Batch](https://github.com/pytorch/torchrec/blob/99e6e669b5a6cc73f6405d654f81427e19fc81b4/torchrec/datasets/utils.py#L28) to represent the input. We use pytree to cast model and inputs to fp64. pytree can not look into a dataclass. My fix is to convert the dataclass to namedtuple to be more pytree friendly
Pull Request resolved: https://github.com/pytorch/pytorch/pull/122012
Approved by: https://github.com/jansel, https://github.com/eellison
