namespace has to be kube-system

In order for this service to be discovered by ServiceMonitor k8s-apps-http, it should belong to namespace kube-system.

manifests/k8s/minikube/kube-scheduler.yaml

@@ -1,6 +1,7 @@
 apiVersion: v1
 kind: Service
 metadata:
+  namespace: kube-system
   name: kube-scheduler-prometheus-discovery
   labels:
     k8s-app: kube-scheduler