Update functions.rst (GH-16468)


This PR will make the following changes to the [_Built-in Functions_](https://docs.python.org/3/library/functions.html) chapter of the library documentation:

- improve hyperlinks in Sphinx roles (trailing 's' belong to hyperlinks).

Automerge-Triggered-By: @csabella
(cherry picked from commit d67279147ace3b63187e5d75a15c345264f39e85)

Co-authored-by: Géry Ogam <gery.ogam@gmail.com>
1 file changed