Description of Problem:
e2e test case: [sig-arch] Managed cluster should ensure pods use downstream images from our release image with proper ImagePullPolicy [Suite:openshift/conformance/parallel] doesn't check all the pods under namespace with 'openshit-' prefix

From the e2e job: https://testgrid.k8s.io/redhat-openshift-ocp-release-4.7-informing#release-openshift-ocp-installer-e2e-openstack-4.7
We can see the pods in `openshift-cluster-csi-drivers` did not use the downstream images(https://gcsweb-ci.apps.ci.l2s4.p1.openshiftapps.com/gcs/origin-ci-test/logs/release-openshift-ocp-installer-e2e-openstack-4.7/1333229426166468608/artifacts/e2e-openstack/pods.json), but this test case was passed.

Version-Release number of selected component (if applicable):

How Reproducible:
Always

Steps to Reproduce:

Actual Results:

Expected Results:

Additional info:
Looks like we ignore the namespace wrongly: https://github.com/openshift/origin/blob/master/test/extended/operators/images.go#L166
Except for this, looks like the step to check the image release version is not correct too, we need to define namespace here. https://github.com/openshift/origin/blob/master/test/extended/operators/images.go#L121