Use matchers in routing tree

manifests/alertmanager-secret.yaml

@@ -40,10 +40,10 @@ stringData:
       "receiver": "Default"
       "repeat_interval": "12h"
       "routes":
-      - "match":
-          "alertname": "Watchdog"
+      - "matchers":
+        - "alertname = Watchdog"
         "receiver": "Watchdog"
-      - "match":
-          "severity": "critical"
+      - "matchers":
+        - "severity = critical"
         "receiver": "Critical"
 type: Opaque