Kubernetes component metrics often have a namespace label themselves,
which is actually relevant. The target namespace label merely informs
where the scrape target is located, which is generally irrelevant for
these specific metrics.
The Prometheus server monitoring Kubernetes should be default cover:
- node exporter
- kubelets
- kube-state-metrics
- apiservers
The version in this commit still has certificate issues with the API
server in minikube. Kubelet scraping likely only works in minikube as it
doesn't seem to use https.