jsonnet/kube-prometheus: Prevent many-to-many matching

If there is more than one prometheus-operator pod, which happens briefly
when we delete the prometheus-operator pod, we can see the errors of
many-to-many matching, this whitelists the labels matching, and excluded
the pod.

jsonnet/kube-prometheus/alerts/alertmanager.libsonnet

@@ -10,7 +10,7 @@
               message: 'The configuration of the instances of the Alertmanager cluster `{{$labels.service}}` are out of sync.',
             },
             expr: |||
-              count_values("config_hash", alertmanager_config_hash{%(alertmanagerSelector)s}) BY (service) / ON(service) GROUP_LEFT() label_replace(prometheus_operator_spec_replicas{%(prometheusOperatorSelector)s,controller="alertmanager"}, "service", "alertmanager-$1", "name", "(.*)") != 1
+              count_values("config_hash", alertmanager_config_hash{%(alertmanagerSelector)s}) BY (service) / ON(service) GROUP_LEFT() label_replace(max(prometheus_operator_spec_replicas{%(prometheusOperatorSelector)s,controller="alertmanager"}) by (name, job, namespace, controller), "service", "alertmanager-$1", "name", "(.*)") != 1
             ||| % $._config,
             'for': '5m',
             labels: {
@@ -31,8 +31,8 @@
             },
           },
           {
-            alert:'AlertmanagerMembersInconsistent',
-            annotations:{
+            alert: 'AlertmanagerMembersInconsistent',
+            annotations: {
               message: 'Alertmanager has not found all other members of the cluster.',
             },
             expr: |||