Update link to tutorial on defining NN modules (#65534)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/65527. Please, see my comment in the issue: https://github.com/pytorch/pytorch/issues/65527#issuecomment-925863193. The file was renamed in https://github.com/pytorch/tutorials/commit/ce58d5904c04c4be10561447e41a153f573a3f93#diff-e5ef486bd89eb38de15752211d9437953681b8caa8f44d7c86bb820d13151df2, but the link in this repository was not updated.
It doesn't change the fact that the old link is still working, but I guess this has to be fixed in [pytorch/tutorials](https://github.com/pytorch/tutorials) instead of here.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/65534
Reviewed By: soulitzer
Differential Revision: D31144269
Pulled By: H-Huang
fbshipit-source-id: f70744a21113b7dc84510e2992d87f0fed793985
