fix the output of router_id with the right id

contrib/terraform/openstack/modules/network/outputs.tf

@@ -1,4 +1,8 @@
 output "router_id" {
+  value = "${openstack_networking_router_v2.k8s.id}"
+}
+
+output "router_internal_port_id" {
   value = "${openstack_networking_router_interface_v2.k8s.id}"
 }