Added a troubleshooting section for webhook (#11099)

* Added a troubleshooting section for webhook

* Update docs/user/guides/build/webhooks.rst

---------

Co-authored-by: Eric Holscher <25510+ericholscher@users.noreply.github.com>

docs/user/guides/build/webhooks.rst

@@ -277,3 +277,21 @@ you can use this payload:
            "date": "{{ build.start_date }}"
        }
    }
+
+Troubleshooting webhooks and payload discovery
+----------------------------------------------
+
+You can use public tools to discover, inspect and test webhook
+integration. These tools act as catch-all endpoints for HTTP requests
+and respond with a 200 OK HTTP status code. You can use these payloads
+to develop your webhook services. You should exercise caution when using
+these tools as you might be sending sensitive data to external tools.
+
+These public tools include:
+
+-  `Beeceptor <https://beeceptor.com/webhook-integration/>`__ to create
+   a temporary HTTPS endpoint and inspect incoming payloads. It lets you
+   respond custom response code or messages from named HTTP mock server.
+-  `Webhook Tester <https://webhook-test.com/>`__ to inspect and debug
+   incoming payloads. It lets you inspect all incoming requests to it’s
+   URL/bucket.