Rename alertmanager vdu-webhook endpoint from alert_vdu to vdu_down

Change-Id: I3c3d343d4682f72a80a62ac0c972769a41665e7c
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/installers/helm/values/alertmanager-values.yaml b/installers/helm/values/alertmanager-values.yaml
index 154af20..4640e3a 100644
--- a/installers/helm/values/alertmanager-values.yaml
+++ b/installers/helm/values/alertmanager-values.yaml
@@ -23,7 +23,7 @@
     - name: default-receiver
     - name: vdu-webhook
       webhook_configs:
-       - url: http://webhook-translator/alert_vdu
+       - url: http://webhook-translator/vdu_down
     - name: scaleout-webhook
       webhook_configs:
        - url: http://webhook-translator/scaleout_vdu