Check port 25 for mailserver locally as the port is blocked on lime2

roles/mailserver_monitoring/templates/zones.d/master/services/mailserver.conf.j2

@@ -3,6 +3,7 @@
 apply Service "smtp" {
     import "generic-service"
     check_command = "smtp"
+    command_endpoint = host.name
     assign where host.name == "{{ inventory_hostname }}"
 }