Add torch to requirements.txt in language-modeling (#12040)
* Add torch to requirements.txt in language-modeling
* Update examples/pytorch/language-modeling/requirements.txt
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>