Fix OKD build for haproxy-router-haproxy28 by pinning to CentOS Stream 9 base

The OKD build was failing because the image inherited an RHEL 10 (CentOS
Stream 10) base through openshift-enterprise-base-rhel9's OKD override
(okd.distgit.branch: rhaos-5.0-rhel-10). The haproxy28 RPM from
rhel-9-server-ose-rpms is an el9 package that requires libpcre.so.1
(PCRE1), which was removed in RHEL/CentOS 10.

Add okd.from.stream: centos_stream9 to match the pattern used by
ose-haproxy-router-base and openshift-enterprise-haproxy-router, which
successfully build for OKD using a CentOS Stream 9 base.

Fixes: origin/scos-5.0:haproxy-router-haproxy28 missing from OKD imagestream
Co-authored-by: Cursor <cursoragent@cursor.com>

rh-pre-commit.version: 2.3.2
rh-pre-commit.check-secrets: ENABLED

Author: ashwindasr

images/ose-haproxy-router-haproxy28.yml

@@ -31,5 +31,7 @@ konflux:
 okd:
   distgit:
     branch: rhaos-5.0-rhel-9
+  from:
+    stream: centos_stream9
   enabled_repos:
   - rhel-9-server-ose-rpms