docs: Network Monitoring SERVICECIDR command for KinD doesn't work for named clusters

[tiswanso]

In the section Monitoring Kubernetes Network Access, the command in the KinD tab for the SERVICECIDR env var assumes the KinD cluster is created without a name.

To avoid the naming issue it should match on the kube-apiserver component label instead like:

export SERVICECIDR=$(kubectl describe pod -n kube-system -l component=kube-apiserver | awk -F= '/--service-cluster-ip-range/ {print $2; }')

[mtardy]

Hello! Good idea, would you like to do a documentation PR to fix that? :)