Add alert resend delay param

- set to 2m
- group_interval default change to 4m

Change-Id: I7fb1cd5700c9d14b064457b06e24d4eee21626ad
Related-bug: PROD-35421
diff --git a/metadata/service/server/standalone.yml b/metadata/service/server/standalone.yml
index 921001c..8e1a942 100644
--- a/metadata/service/server/standalone.yml
+++ b/metadata/service/server/standalone.yml
@@ -10,6 +10,7 @@
     prometheus_storage_retention: "4320h"
     prometheus_server_bind_port: 9090
     prometheus_cors_origin: ".*"
+    prometheus_alert_resend_delay: "2m"
   prometheus:
     server:
       enabled: true