Aggregate functions description page should link to Aggregate Functions list page

Aggregate functions description page should link to Aggregate Functions list page

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/16/tutorial-agg.html
Description:

There are two documentation pages with the same title "Aggregate Functions".
One describes what they are and one lists all of them. The two pages should
provide links to each other.

https://www.postgresql.org/docs/current/tutorial-agg.html

and

https://www.postgresql.org/docs/current/functions-aggregate.html