torcontrol: Use the default/standard network port for Tor hidden services, even if the internal port is set differently

Summary:
PR description:

Currently, the hidden service is published on the same port as the public listening port.
But if a non-standard port is configured, this can be used to guess (pretty reliably) that the public IP and the hidden service are the same node.

This is a backport of Core PR15651

Test Plan: ninja all check-all

Reviewers: #bitcoin_abc, majcosta

Reviewed By: #bitcoin_abc, majcosta

Differential Revision: https://reviews.bitcoinabc.org/D8368