Remove unused if in `default_template.go`

[renepupil]

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[renepupil]

I strongly suggest splitting the template into multiple lines, just like regular code:

{{- define "default.message" -}}
    {{- if gt (len .Alerts.Firing) 0 -}}
        **Firing**
        {{- template "__text_alert_list" .Alerts.Firing -}}
    {{- end -}}
    {{- if gt (len .Alerts.Resolved) 0 -}}
        **Resolved**
        {{- template "__text_alert_list" .Alerts.Resolved -}}
    {{- end -}}
{{- end -}}

[renepupil]

MEMO: Same also in {{- define "teams.default.message" -}} block.