kube-promethes: Fix default serviceMonitorSelector

jsonnet/kube-prometheus/prometheus/prometheus.libsonnet

@@ -21,7 +21,7 @@ local k = import 'ksonnet/ksonnet.beta.3/k.libsonnet';
       replicas: 2,
       rules: {},
       renderedRules: {},
-      namespaces: ["default", "kube-system",$._config.namespace],
+      namespaces: ['default', 'kube-system', $._config.namespace],
     },
   },
 
@@ -166,8 +166,8 @@ local k = import 'ksonnet/ksonnet.beta.3/k.libsonnet';
           version: $._config.versions.prometheus,
           baseImage: $._config.imageRepos.prometheus,
           serviceAccountName: 'prometheus-' + $._config.prometheus.name,
-          serviceMonitorSelector: selector.withMatchExpressions({ key: 'k8s-app', operator: 'Exists' }),
-          serviceMonitorNamespaceSelector: selector.withMatchExpressions({}),
+          serviceMonitorSelector: {},
+          serviceMonitorNamespaceSelector: {},
           nodeSelector: { 'beta.kubernetes.io/os': 'linux' },
           ruleSelector: selector.withMatchLabels({
             role: 'alert-rules',