DOC: MultiIndex.is_lexsorted not linked
#### Location of the documentation

https://pandas.pydata.org/docs/dev/reference/api/pandas.MultiIndex.html?highlight=is_lexsorted

#### Documentation problem

On the API page for `MultiIndex`, `is_lexsorted` does not link to an API page for that method. That method has been deprecated and does not contain a docstring, perhaps that is why there is no link?

#### Suggested fix for documentation

Since this method is deprecated, suggest removing `is_lexsorted` from the list of methods on the `MultiIndex` API page. Alternatively could add a docstring and API page.

What is preferred?