NLB-6555 Updated sample k8s service manifest for NGINXaaS Load Balancer for Kubernetes (#461)

Filled in missing port field. This should make it easier for users to adapt manifest to their use case.

Author: arussellf5

content/nginxaas-azure/quickstart/loadbalancer-kubernetes.md

@@ -278,6 +278,7 @@ spec:
   type: NodePort
   ports:
     - targetPort: http
+      port: 80
       protocol: TCP
       # The port name helps connect to NGINXaaS. It must be prefixed with either `http-` or `stream-`
       # and the rest of the name must match the name of an upstream in that context.