Description of problem:
Recently in CentOS CI we started migration from on-prem baremetal machines to EC2 instances, both VMs and metal nodes for workloads which require access to KVM - where systemd being one of such workloads.

While migrating our systemd jobs over to metal machines, I stumbled across quite a conundrum: the metal machines can't be reasonably rebooted, since the reboot takes 10 - 20 minutes, so we have to "live" with the kernel provided by the latest AMI - in this case it's CentOS Stream 8. However, the kernel in the C8S AMI appears to be quite out of date:

1. uname -r
   4.18.0-305.3.1.el8.x86_64

Packages on one of the C8S mirrors:

[ ] kernel-4.18.0-305.10.2.el8_4.x86_64.rpm 2021-07-20 21:12 5.9M
[ ] kernel-4.18.0-305.12.1.el8_4.x86_64.rpm 2021-08-11 05:46 5.9M
[ ] kernel-4.18.0-305.17.1.el8_4.x86_64.rpm 2021-09-08 17:47 5.9M
[ ] kernel-4.18.0-305.19.1.el8_4.x86_64.rpm 2021-09-15 20:50 5.9M
[ ] kernel-4.18.0-305.25.1.el8_4.x86_64.rpm 2021-11-03 12:55 5.9M
[ ] kernel-4.18.0-315.el8.x86_64.rpm 2021-06-28 22:45 6.4M
[ ] kernel-4.18.0-326.el8.x86_64.rpm 2021-07-29 00:48 6.8M
[ ] kernel-4.18.0-331.el8.x86_64.rpm 2021-08-19 20:23 6.9M
[ ] kernel-4.18.0-338.el8.x86_64.rpm 2021-08-27 20:43 7.0M
[ ] kernel-4.18.0-348.2.1.el8_5.x86_64.rpm 2021-11-17 17:09 7.0M
[ ] kernel-4.18.0-348.7.1.el8_5.x86_64.rpm 2021-12-22 15:51 7.0M
[ ] kernel-4.18.0-348.el8.x86_64.rpm 2021-10-20 18:52 7.0M
[ ] kernel-4.18.0-358.el8.x86_64.rpm 2022-01-10 16:54 7.5M
[ ] kernel-4.18.0-365.el8.x86_64.rpm 2022-02-10 18:54 7.7M
[ ] kernel-4.18.0-373.el8.x86_64.rpm 2022-03-22 18:34 8.0M
[ ] kernel-4.18.0-383.el8.x86_64.rpm 2022-04-20 22:10 8.1M
[ ] kernel-4.18.0-394.el8.x86_64.rpm 2022-06-03 16:54 8.3M
[ ] kernel-4.18.0-408.el8.x86_64.rpm 2022-07-19 16:50 8.5M

This is quite unfortunate, since the sytemd-networkd test suite requires extra kernel modules from the kernel-modules-extra package, which is no longer available on mirrors for the kernel version used by the C8S AMI.

I'm not sure how often the CentOS Stream AMIs are supposed to be updated, but I guess it should be relatively often, given that CentOS Stream is basically a rolling release now?

Additional info:
Original CentOS Infra ticket: https://pagure.io/centos-infra/issue/873