Rename the Master Node label to node-role.kubernetes.io/control-plane

[teamc-tommy]

Describe the bug

Since the K8S 1.24+, the label "node-role.kubernetes.io/master" is removed.
The NLK watch still using the deprecated label for checking the control-plane

To reproduce

Steps to reproduce the behavior:

1. Deploy nginx_loadbalancer_kubernetes
2. The Master Node (control plane) node is listed in the HTTP upstream
3. Only worker should be in the upstream list

Expected behavior

The NLK watcher should use the control plane label. "node-role.kubernetes.io/control-plane"

Your environment

Kubernetes 1.31.1
nginx_loadbalancer_kubernetes 178

Additional context

Source