Expose custom metrics

[joelddiaz]

Set up the pieces to allow reporting custom metrics. https://book.kubebuilder.io/reference/metrics.html

Start by exposing a count of the number of MondooAuditConfig resources as the first custom metric. Since this is not something that can easily be calculated during a Reconcile() loop, it may make more sense to set up a controller that just periodically runs to calculate the metrics to be reported.

https://github.com/openshift/cloud-credential-operator/blob/master/pkg/operator/metrics/ can be used as an example of setting up a controller that doesn't watch for a specific resource, but just runs at a set interval.