remove kube-apiserver --insecure-port usage

[neolit123]

the flag is being removed after a long deprecation period:
kubernetes/kubernetes#91506

in kubeadm we are passing:
--insecure-port=0 in the api server static pod.

the flag became a no-op in 1.20:
kubernetes/kubernetes#95856

it will be removed in 1.24:
https://github.com/kubernetes/kubernetes/pull/95856/files#diff-3149c6ede53e3a658bbcf11f1456f2ac955ae49db5ab66ee9e13f883488349d3R151

kubeadm can remove it earleir

related to:
#2207

NOTE

this PR might do the change in kubeadm as well:
kubernetes/kubernetes#95522

[RA489]

/assign

[liggitt]

critically, kubeadm should not stop setting this flag until a kubernetes version that removes insecure serving ability... in all currently released versions, not specifying the flag accepts the default behavior of enabling the insecure port

[pacoxu]

/assign

Flag --insecure-port has been deprecated, **This flag has no effect now and will be removed in v1.24.**
Error: invalid port value 28080: only zero is allowed

As this flag has no effect, we can just remove it in kubeadm side in 1.22 now.

[neolit123]

@pacoxu

i see that for the kube-apiserver the change was made in 1.20:
kubernetes/kubernetes@cfc2b33

kubeadm can deploy N and N-1 control-plane. so kubeadm 1.22 can deploy 1.22 and 1.21 kube-apiserver.
given the flag no longer has effect in 1.21, we can remove it for the kube-apiserver that kubeadm 1.22 manages.

for the KCM and KS i see the insecure flags are becoming no-op in 1.22:
kubernetes/kubernetes#96216
kubernetes/kubernetes#96345

thus we can delay the kubeadm change for KCM and KS to 1.23, to avoid branching:
#2207