BUG #18508: Not all packages are present in the repo on rhel 8

The following bug has been logged on the website:

Bug reference: 18508
Logged by: David M. Pulkowski
Email address: dpulkowski(at)uwhealth(dot)org
PostgreSQL version: 16.3
Operating system: RHEL 8
Description:

https://www.postgresql.org/download/linux/redhat/

When following this for setting up the repo. All works fine for rhel8 &
rhel9.
Yet, what dnf sees on the repo differs in rhel8 vs rhel9 and I cant seem to
figure why or what is wrong, as the process of adding the repo was the
same.
If I browse to the repo in a web-browser I can see the package there, but
dnf can see it on rhel8?

RHEL8
```
cat /etc/redhat-release
Red Hat Enterprise Linux release 8.10 (Ootpa)
```
Rhel 8 (abridged list)
```
yum repolist

pgdg-common
PostgreSQL common RPMs for RHEL / Rocky / AlmaLinux 8 -
x86_64
pgdg12
PostgreSQL 12 for RHEL / Rocky / AlmaLinux 8 - x86_64
pgdg13
PostgreSQL 13 for RHEL / Rocky / AlmaLinux 8 - x86_64
pgdg14
PostgreSQL 14 for RHEL / Rocky / AlmaLinux 8 - x86_64
pgdg15
PostgreSQL 15 for RHEL / Rocky / AlmaLinux 8 - x86_64
pgdg16
PostgreSQL 16 for RHEL / Rocky / AlmaLinux 8 - x86_64
```
List packages in repo and search for posgres16 on rhel 8:
```
dnf repository-packages pgdg16 list | grep postgresql16
postgresql16-libs.x86_64 16.3-3PGDG.rhel8
@pgdg16
postgresql16-devel.x86_64 16.3-3PGDG.rhel8
pgdg16
postgresql16-llvmjit.x86_64 16.3-3PGDG.rhel8
pgdg16
postgresql16-odbc.x86_64 16.00.0000-1PGDG.rhel8
pgdg16
postgresql16-tcl.x86_64 3.0.0-2.rhel8.1
pgdg16
```

RHEL 9
```
cat /etc/redhat-release
Red Hat Enterprise Linux release 9.3 (Plow)
```

Same setup but on rhel 9 (abridged list)
```
yum repolist

pgdg-common
PostgreSQL common RPMs for RHEL / Rocky / AlmaLinux 9 -
x86_64
pgdg12
PostgreSQL 12 for RHEL / Rocky / AlmaLinux 9 - x86_64
pgdg13
PostgreSQL 13 for RHEL / Rocky / AlmaLinux 9 - x86_64
pgdg14
PostgreSQL 14 for RHEL / Rocky / AlmaLinux 9 - x86_64
pgdg15
PostgreSQL 15 for RHEL / Rocky / AlmaLinux 9 - x86_64
pgdg16
PostgreSQL 16 for RHEL / Rocky / AlmaLinux 9 - x86_64
```
List packages in repo and search for posgres16 on rhel 9:
```
dnf repository-packages pgdg16 list | grep postgresql16
Repository ol9_oracle_instantclient is listed more than once in the
configuration
postgresql16.x86_64 16.3-1PGDG.rhel9
@pgdg16
postgresql16-devel.x86_64 16.3-1PGDG.rhel9
@pgdg16
postgresql16-libs.x86_64 16.3-1PGDG.rhel9
@pgdg16
postgresql16-contrib.x86_64 16.3-1PGDG.rhel9
pgdg16
postgresql16-docs.x86_64 16.3-1PGDG.rhel9
pgdg16
postgresql16-llvmjit.x86_64 16.3-1PGDG.rhel9
pgdg16
postgresql16-odbc.x86_64 16.00.0000-1PGDG.rhel9
pgdg16
postgresql16-plperl.x86_64 16.3-1PGDG.rhel9
pgdg16
postgresql16-plpython3.x86_64 16.3-1PGDG.rhel9
pgdg16
postgresql16-pltcl.x86_64 16.3-1PGDG.rhel9
pgdg16
postgresql16-server.x86_64 16.3-1PGDG.rhel9
pgdg16
postgresql16-tcl.x86_64 3.0.0-2.rhel9.1
pgdg16
postgresql16-test.x86_64 16.3-1PGDG.rhel9
pgdg16
```