gracefully handle missing severity

query_alertmanager.py

@@ -34,7 +34,7 @@ def get_alerts(url: str, password: str, user: str = "admin") -> dict:
             # pp.pprint(alert)
 
             name = alert["labels"]["alertname"]
-            severity = alert["labels"]["severity"]
+            severity = alert["labels"].get("severity", "unknown")
             instance = alert["labels"].get("instance", "")
             alert_state = alert["status"]["state"]
             release_name = alert["labels"].get("release_name", "")