DOC : Typo fix in userguide/Styling
- [ ] closes #xxxx
- [ ] tests added / passed
- [ ] passes `black pandas`
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

Fixed a typo in the user-guide/Styling: https://pandas-docs.github.io/pandas-docs-travis/user_guide/style.html#Sharing-Styles

In the line:
`Notice that you’re able share the styles even though they’re data aware. The styles are re-evaluated on the new DataFrame they’ve been used upon.`
thanks @koushikgk 