Fix lint

Author: Joe Cummings

CONTRIBUTING.md

@@ -59,14 +59,14 @@ Each API and class should be clearly documented. Well-documented code is easier
 * All files under the [deep dives directory](docs/source/deep_dives) contain "deep-dive" tutorials
 * All files under the [tutorials directory](docs/source/tutorials) contain regular tutorials
 
-Documentation is written in [RST](https://www.sphinx-doc.org/en/master/usage/restructuredtext/basics.html) format. 
+Documentation is written in [RST](https://www.sphinx-doc.org/en/master/usage/restructuredtext/basics.html) format.
 
 ### Adding a new class/method to the API References
 Once you've added an API that is meant to be exposed publically, you should add it to the appropriate rst file. For example, any new API within the [configs/](torchtune/configs)
 directory should be added to `api_ref_configs.rst`, [data/](torchtune/data) should be added to `api_ref_data.rst`, [datasets](torchtune/datasets) should be added to
-`api_ref_datasets.rst`, and so on. To add, it's as simple as adding the name of the exposed API somewhere in the appropriate RST file. 
+`api_ref_datasets.rst`, and so on. To add, it's as simple as adding the name of the exposed API somewhere in the appropriate RST file.
 
-All code written within the docstring of the class or method will be correctly rendered there. 
+All code written within the docstring of the class or method will be correctly rendered there.
 
 > Note: Our RST theme expects code to be specified using double backticks instead of single. Eg: ``hidden_dim``. Single backticks will be rendered as italics instead of as "code".