prometheus: Initialize mgmt_checkapply_total metrics

It is recommended by Prometheus to initialize metrics:

https://prometheus.io/docs/practices/instrumentation/#avoid-missing-metrics

This commits initialize the mgmt_checkapply_total metric
for each registered resource.

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>

lib/main.go

@@ -269,6 +269,10 @@ func (obj *Main) Run() error {
 		if err := prom.Start(); err != nil {
 			return errwrap.Wrapf(err, "can't start initiate Prometheus instance")
 		}
+
+		if err := prom.InitKindMetrics(resources.RegisteredResourcesNames()); err != nil {
+			return errwrap.Wrapf(err, "can't initialize kind-specific prometheus metrics")
+		}
 	}
 
 	if !obj.NoPgp {