Docs: don't override __module__

[adamjstewart]

In Sphinx 3, import aliases would throw off intersphinx:

• py:class reference target not found: torch.utils.data.dataset.Dataset pytorch/pytorch#60979
• https://stackoverflow.com/questions/40018681

This was supposedly fixed in Sphinx 4:

• sphinx.ext: incompatibility between autodoc and viewcode sphinx-doc/sphinx#9395

I was finally able to upgrade PyTorch and torchvision to use Sphinx 5:

• Docs: build with Sphinx 5 pytorch/pytorch#70309
• Docs: build with Sphinx 5 pytorch/vision#5121

So in theory, we should no longer need to override __module__. Fingers crossed that the doc tests pass and the docs look okay!

[adamjstewart]

Well, this doesn't work at all. Will open an issue with the Sphinx devs...