Module torch has no attribute minimum for modeling_big_bird.py
Hello

I came across `module 'torch' has no attribute minimum` from the following two lines 

1.https://github.com/huggingface/transformers/blob/73fde1defe9be259a47b9024525882f3ec420994/src/transformers/models/big_bird/modeling_big_bird.py#L662

2.https://github.com/huggingface/transformers/blob/73fde1defe9be259a47b9024525882f3ec420994/src/transformers/models/big_bird/modeling_big_bird.py#L796

I think `torch.minimum` should be replaced with `torch.min`
`torch.minimum` was only added in August 2020 to PyTorch, so `torch.minimum` is probably only part of torch 1.7+. To work for previous versions, it should indeed be replaced by `torch.min`.

The README of this repository states that: "This repository is tested on Python 3.6+, Flax 0.3.2+, PyTorch 1.3.1+ and TensorFlow 2.3+." 

cc @vasudevgupta7<|||||>This bug is making it impossible to use BigBird in combination with AWS HuggingFace setup as that one is currently restricted to Pytorch 1.6. (https://huggingface.co/blog/the-partnership-amazon-sagemaker-and-hugging-face) 

Are there any plans to fix the modeling_big_bird.py so that it is backward compatible or agree with AWS on support of never version of Pytorch for HuggingFace containers?<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

Please note that issues that do not follow the [contributing guidelines](https://github.com/huggingface/transformers/blob/master/CONTRIBUTING.md) are likely to be ignored.