Fix shell escaping for ovn-nbctl address_set lookup in test 72028

The PodSelector external_id format contains spaces (e.g.,
"policy-group.network.openshift.io/host-network: ,") which caused
bash word-splitting when using backslash escaping. Switch to
single-quote wrapping to preserve the argument as a single token.

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

Author: anuragthehatter

test/otp/util.go

@@ -555,8 +555,8 @@ func getHostNetworkIPsinNBDB(oc *CLI, nodeName string, ipFamily string) []string
 	o.Expect(ovnKubePod).ShouldNot(o.Equal(""))
 
 	candidateExternalIDs := []string{
-		`external_ids:\"k8s.ovn.org/id\"=\"default-network-controller:PodSelector:LS\{ML:\{policy-group.network.openshift.io/host-network: ,\},\}_LS\{\}_LNM:` + ipFamily + `\"`,
-		`external_ids:\"k8s.ovn.org/id\"=\"default-network-controller:Namespace:openshift-host-network:` + ipFamily + `\"`,
+		`'external_ids:"k8s.ovn.org/id"="default-network-controller:PodSelector:LS{ML:{policy-group.network.openshift.io/host-network: ,},}_LS{}_LNM:` + ipFamily + `"'`,
+		`'external_ids:"k8s.ovn.org/id"="default-network-controller:Namespace:openshift-host-network:` + ipFamily + `"'`,
 	}
 
 	var cmdOutput string