Re-enable local registry mirrors for old container images

[stuggi]

For container tags with dates before 20251006 (old registry), use site-specific local mirrors (rhos-qe-mirror.lab.eng.*.redhat.com:5002) to avoid image pull timeouts in CI. For newer containers, override with registry.stage.redhat.io since the new registry has no geo mirrors.

Jira: OSPRH-31105

[stuggi]

tested with 16.2 and 17.1 jobs that the older base version now correct use the local mirror and when running the update they use the new registry.

[abays]

/lgtm

[abays]

Failure looks like a hiccup:

TASK [oc_local : Download https://download.devel.redhat.com/rcm-guest/puddles/OpenStack/16.2-RHEL-8/latest_cdn/container_image_prepare.yaml] ***
Friday 12 June 2026  17:07:50 +0000 (0:00:01.911)       0:00:03.777 *********** 
�[0;31mfatal: [localhost]: FAILED! => {�[0m
�[0;31m    "changed": false,�[0m
�[0;31m    "content": "",�[0m
�[0;31m    "elapsed": 15,�[0m
�[0;31m    "redirected": false,�[0m
�[0;31m    "status": -1,�[0m
�[0;31m    "url": "https://download.devel.redhat.com/rcm-guest/puddles/OpenStack/16.2-RHEL-8/latest_cdn/container_image_prepare.yaml"�[0m
�[0;31m}�[0m
�[0;31m�[0m
�[0;31mMSG:�[0m
�[0;31m�[0m
�[0;31mStatus code was -1 and not [200]: Request failed: <urlopen error [Errno -2] Name or service not known>�[0m