Underline formatting typo

[dmitmatveev]

Describe the bug

See the photo below: text starts to be underline formatted on the sentence "This is only valid for datetime-like indexes." and that continues, even on python-code.

How to fix?

• like indexes.**<u/> -> like indexes.**</u>

To Reproduce

See rendered version nbviewer - data_analytics_task.ipynb

Expected behavior

Text-underline formatting should be ended on the "... indexes."

Additional context