[addrman] Fix Connected() comment

Summary:
This is a backport of core#20291 [2/2]
https://github.com/bitcoin/bitcoin/pull/20291/commits/0bfce9dc46234b196a8b3679c21d6f8455962495

Depends on D10698

Test Plan: ninja all check-all

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Subscribers: Fabien

Differential Revision: https://reviews.bitcoinabc.org/D10699