BUG #17347: pg_upgrade: analyze_new_cluster script analyzes wrong cluster

The following bug has been logged on the website:

Bug reference:      17347
Logged by:          Mathias Kunter
Email address:      mathiaskunter@gmail.com
PostgreSQL version: 12.9
Operating system:   Debian 10.11
Description:

When upgrading a PostgreSQL cluster with pg_upgrade (tested while upgrading
from 11.14 to 12.9, but supposedly affects all versions), and the --new-port
argument is used to specify a new port number for the upgraded cluster, then
the generated analyze_new_cluster script will connect to and analyze a
different cluster instead of the upgraded one.

The vacuumdb command found within the analyze_new_cluster script should
explicitly specify the port number of the upgraded cluster, so that it will
actually analyze the correct cluster after the upgrade.