Pass in Alerta authentication details for Alertmanager to send alerts with

Related-PROD: PROD-35884
Change-Id: I5ee52fb3fd81a48464414102d909baaeb4a1c18d
diff --git a/prometheus/alerta/init.yml b/prometheus/alerta/init.yml
index 6e16b63..2e82f44 100644
--- a/prometheus/alerta/init.yml
+++ b/prometheus/alerta/init.yml
@@ -1,5 +1,5 @@
 classes:
-  - service.prometheus.alerta
+- service.prometheus.alerta
 parameters:
   prometheus:
     alerta: