[Release-1.19] Restoration fails on etcd only nodes due to invalid state of loadbalancers

[galal-hussein]

Environmental Info:
RKE2 Version: v1.19.x

Cluster Configuration:

• 1 etcd only node server
• 1 controlplane node servers

Describe the bug:
upon restoring on an existing etcd only node, it tries to setup internal load balancer with existing configuration, and tries to connect to old supervisor servers, which may or may not exist and fails to restore wiht the following error:

msg=\"Waiting to retrieve agent configuration; server is not ready: Get \\\"https://127.0.0.1:6444/v1-rke2/serving-kubelet.crt\\\": context deadline exceeded (Client.Timeout exceeded while awaiting headers)\""
``

[rancher-max]

Validated on v1.19.14-rc1+rke2r1

Confirmed during restoration load balancer gets reset:

...
INFO[0000] Running load balancer 127.0.0.1:6444 -> [127.0.0.1:9345] 
...
INFO[0000] Running load balancer 127.0.0.1:6445 -> [127.0.0.1:6443] 
...

Then when restarting the service afterwards without restoration flags, the loadbalancer looks for the control-plane again:

...
Aug 24 18:42:25 ip-172-31-28-36 rke2[6247]: time="2021-08-24T18:42:25Z" level=info msg="Running load balancer 127.0.0.1:6444 -> [172.31.28.195:9345 127.0.0.1:9345]"
...