Hello Jason,
I belive you can use Git ignore for the files (Not 100% sure it will work but I've seen .gitignore files scattered in my project which I assume were generated by Mendix).
See https://git-scm.com/docs/gitignore for documentation.
My projects seem to contain a gitignore file in \deployment\web\styles\sass\lib which you can also use as a template.
Hope this helps