Export controller metrics like kubebuilder

[tamalsaha]

https://book.kubebuilder.io/beyond_basics/controller_metrics.html

[tamalsaha]

• https://github.com/kubernetes-sigs/controller-runtime/blob/master/pkg/metrics/client_go_adapter.go
• https://github.com/kubernetes-sigs/controller-runtime/blob/master/pkg/internal/controller/metrics/metrics.go