fix(manifests): remove hardcoded preprod hostname from mpp-openshift route

The ambient-api-server Route in the mpp-openshift overlay had a hardcoded
spec.host pointing to the preprod cluster ingress. Removing spec.host lets
OpenShift's router auto-assign the correct hostname for the target environment.

Fixes: RHOAIENG-56570

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: Ambient Code Bot

components/manifests/overlays/mpp-openshift/ambient-api-server-route.yaml

@@ -7,7 +7,6 @@ metadata:
     component: api
     shard: internal
 spec:
-  host: ambient-api-server-ambient-code--runtime-int.internal-router-shard.mpp-w2-preprod.cfln.p1.openshiftapps.com
   to:
     kind: Service
     name: ambient-api-server