webhooks: Pass helpful strings to UnsupportedWebhookEventTypeError.

This helps understand _what_ event type was not supported.

zerver/webhooks/harbor/view.py

@@ -65,7 +65,7 @@ def handle_scanning_completed_event(
     scan_results = ""
     scan_overview = payload["event_data"]["resources"][0]["scan_overview"]
     if "application/vnd.security.vulnerability.report; version=1.1" not in scan_overview:
-        raise UnsupportedWebhookEventTypeError("Unsupported harbor scanning webhook payload")
+        raise UnsupportedWebhookEventTypeError(str(list(scan_overview.keys())))
     scan_summaries = scan_overview["application/vnd.security.vulnerability.report; version=1.1"][
         "summary"
     ]["summary"]

zerver/webhooks/linear/view.py

@@ -146,7 +146,7 @@ def get_topic(user_specified_topic: Optional[str], event: str, payload: WildValu
         issue_id = payload["data"]["id"].tame(check_string)
         return issue_id
 
-    raise UnsupportedWebhookEventTypeError("unknown event type")
+    raise UnsupportedWebhookEventTypeError(event)
 
 
 def get_event_type(payload: WildValue) -> Optional[str]:

zerver/webhooks/sentry/view.py

@@ -228,7 +228,7 @@ def handle_issue_payload(
         body = ISSUE_IGNORED_MESSAGE_TEMPLATE.format(**context)
 
     else:
-        raise UnsupportedWebhookEventTypeError("unknown-issue-action type")
+        raise UnsupportedWebhookEventTypeError(f"{action} action")
 
     return (topic, body)