[kube-prometheus-stack] inhibit InfoInhibitor alerts by default (#3964)

Signed-off-by: ANGkeith <[email protected]>

charts/kube-prometheus-stack/values.yaml

@@ -311,6 +311,8 @@ alertmanager:
           - 'severity = info'
         equal:
           - 'namespace'
+      - target_matchers:
+          - 'alertname = InfoInhibitor'
     route:
       group_by: ['namespace']
       group_wait: 30s
@@ -320,7 +322,7 @@ alertmanager:
       routes:
       - receiver: 'null'
         matchers:
-          - alertname =~ "InfoInhibitor|Watchdog"
+          - alertname = "Watchdog"
     receivers:
     - name: 'null'
     templates: