Make the TooManyLoginFailures alert less noisy

roles/ai3-prometheus/templates/rules/alerts_auth.conf.yml

@@ -9,7 +9,7 @@ groups:
       #
       # Services that are excluded here should be added to NoLogins.
       - alert: TooManyLoginFailures
-        expr: service:auth_requests_ok:ratio{exported_service!="smtp"} < 0.2
+        expr: service:auth_requests_ok:ratio{exported_service!="smtp"} < 0.2 and service:auth_requests_ok:delta10m{exported_service!="smtp"} > 5
         for: 10m
         labels:
           severity: page