cert tests: skip TLS certificate tests on ROSA clusters

Add IsRosaCluster() function to test/extended/util/framework.go and
use it to skip TLS certificate tests on ROSA clusters, similar to how
we skip for MicroShift and Hypershift.

ROSA clusters do not auto-collect TLS certificates the same way as
standard OpenShift clusters.

Author: wangke19

test/extended/operators/certs.go

@@ -105,6 +105,9 @@ var _ = g.Describe(fmt.Sprintf("[sig-arch][Late][Jira:%q]", "kube-apiserver"), g
 		if ok, _ := exutil.IsHypershift(ctx, configClient); ok {
 			g.Skip("hypershift does not auto-collect TLS.")
 		}
+		if ok, _ := exutil.IsRosaCluster(oc); ok {
+			g.Skip("ROSA does not auto-collect TLS.")
+		}
 		var err error
 		onDiskPKIContent := &certgraphapi.PKIList{}
 

test/extended/util/framework.go

@@ -2328,6 +2328,16 @@ func IsMicroShiftCluster(kubeClient k8sclient.Interface) (bool, error) {
 	return true, nil
 }
 
+// IsRosaCluster returns "true" if a cluster is ROSA,
+// "false" otherwise.
+func IsRosaCluster(oc *CLI) (bool, error) {
+	product, err := oc.WithoutNamespace().AsAdmin().Run("get").Args("clusterclaims/product.open-cluster-management.io", "-o=jsonpath={.spec.value}").Output()
+	if err != nil {
+		return false, nil
+	}
+	return strings.Compare(product, "ROSA") == 0, nil
+}
+
 func IsTwoNodeFencing(ctx context.Context, configClient clientconfigv1.Interface) bool {
 	infrastructure, err := configClient.ConfigV1().Infrastructures().Get(ctx, "cluster", metav1.GetOptions{})
 	if err != nil {