Prometheus description - incompatible types for comparison

Hi,

Alertmanager warning description for UNIVENTION_JOINSTATUS is not correct.

The template for description is set as default:

The join status of the system is incorrect:
{{ range query "univention_join_status" }}
	univention_join_status has value {{.Value}}
	{{if or (eq .Value -1) (eq .Value 1)}}
	=> /etc/machine.secret not found - system not joined yet?
	{{end}}
	{{if (eq .Value 2)}}
	=> ldapsearch auth failed
	{{end}}
	{{if (eq .Value 3)}}
	=> ldapsearch auth or TLS failed
	{{end}}
	{{if (eq .Value 4)}}
	=> Cannot find /usr/share/univention-join/.joined or /var/univention-join/joined
	{{end}}
{{ end }}

The mail which is sended by alertmanager throws error:

Annotations
description = <error expanding template: error executing template __alert_UNIVENTION_JOINSTATUS: template: __alert_UNIVENTION_JOINSTATUS:4:10: executing "__alert_UNIVENTION_JOINSTATUS" at <eq .Value -1>: error calling eq: incompatible types for comparison>
title = check if system has been joined successfully

I remember that I did not change anything in that description. Is that a bug?