BUG&TST: HTML formatting error in Styler.render() in rowspan attribute
- [x] closes [#38234](https://github.com/pandas-dev/pandas/issues/38234)
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [x] whatsnew entry

Hello @JoseNavy! Thanks for updating this PR. We checked the lines you've touched for [PEP 8](https://www.python.org/dev/peps/pep-0008) issues, and found:





There are currently no PEP 8 issues detected in this Pull Request. Cheers! :beers: 

##### Comment last updated at 2020-12-22 18:13:36 UTC lgtm ping on greenish The Travis check didn't pass and after checking why, I don't see a clear error on what went wrong. All the other checks did pass, can you help me with this? @jreback   thanks @JoseNavy the travis CI is acting up, unrelated @meeseeksdev backport 1.2.x