BUG #18282: repomd.xml signature could not be verified for pgdg-common

The following bug has been logged on the website:

Bug reference:      18282
Logged by:          Mike Accola
Email address:      michael.accola@hpe.com
PostgreSQL version: 15.4
Operating system:   RHEL 7
Description:

We just started seeing this repo error for pgdg-common recently when trying
to do updates.  

Importing GPG key 0x442DF0F8:
 Userid     : "PostgreSQL RPM Building Project
<pgsql-pkg-yum@postgresql.org>"
 Fingerprint: 68c9 e2b9 1a37 d136 fe74 d176 1f16 d2e1 442d f0f8
 Package    : pgdg-redhat-repo-42.0-35PGDG.noarch (@pgdg-common)
 From       : /etc/pki/rpm-gpg/RPM-GPG-KEY-PGDG
pgdg-common/7Server/x86_64/signature                     | 2.9 kB     00:09
!!! 
https://download.postgresql.org/pub/repos/yum/common/redhat/rhel-7Server-x86_64/repodata/repomd.xml:
[Errno -1] repomd.xml signature could not be verified for pgdg-common
Trying other mirror.

Further experimenting showed there is a similar problem for pgdg15, pgdg14,
pgdg13, and pgdg12.