ENH: kw `names` to `Styler.hide_index`
adds an item to #41649 and #41693

Im ambiguous about this feature but for better compatability when refactoring `DataFrame.to_html` and `DataFrame.to_latex` to use `Styler` it is needed.

![Screen Shot 2021-09-01 at 19 18 49](https://user-images.githubusercontent.com/24256554/131715321-34925946-f42c-4c79-ae9e-e07fc9a1381a.png)
