[DOC] Tautological/recursive `See also` link

[rs2]

https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.isnull.html#pandas.DataFrame.isnull

Please assign to me.

[topper-123]

I don't think this is self-referencing: The first pandas.DataFrame.isnull references the page, while the second pandas.DataFrame.isnull references the anchor inside the page.

I'm closing, but yu can open again, if you misunderstand each other.