Consider inheritance in type checking for tensors
Author: daemyung
Pull request: yes

# What does this PR do?

Add an additional check to bypass type assertion when both tensors are torch.Tensor instances.

# Why this PR is needed.

I have defined a class which inherit torch.Tensor to keep additional information. Since it inherits from torch.Tensor, it should be acceptable to treat it as torch.Tensor. However the current code requires an exact type match, which doesn't handle my case. I believe this strict type checking does not satisfy to the priciple of OOP.

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- [x] Did you write any new necessary tests?


## Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
members/contributors who may be interested in your PR.

@muellerzr and @SunMarc

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Comments:
@SunMarc Thanks. I have fixed the quality issue. Let's wait CI is passed.

@SunMarc CI is passed. Please merge it. Thanks.

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_31378). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

@muellerzr and @SunMarc Could you merge this PR?

Yes! No worries