Add CNO test extension binary

Register the cluster-network-operator OTE binary so openshift-tests
can discover and run CNO-specific e2e tests from the payload.

Based on openshift/cluster-network-operator#3015

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: anuragthehatter

pkg/test/extensions/binary.go

@@ -293,6 +293,10 @@ var extensionBinaries = []TestBinary{
 		imageTag:   "cluster-storage-operator",
 		binaryPath: "/usr/bin/cluster-storage-operator-tests-ext.gz",
 	},
+	{
+		imageTag:   "cluster-network-operator",
+		binaryPath: "/usr/bin/cluster-network-operator-tests-ext.gz",
+	},
 	{
 		imageTag:   "cluster-version-operator",
 		binaryPath: "/usr/bin/cluster-version-operator-tests.gz",