Merge pull request #4023 from replicatedhq/docs/failure-alert-contacts

[! wait to merge !] Document failure alert contact for webhook notification subscriptions

Author: alicenstar

docs/vendor/event-notifications-create.mdx

@@ -74,6 +74,12 @@ To create an event notification subscription:
 
          The test result displays the HTTP status code and response time, or an error message with troubleshooting guidance. If you configured a signing secret, the test request is signed with HMAC-SHA256 so you can also verify your signature validation logic.
 
+      1. (Optional) In the **Failure alert contact** field, enter the email address to notify when webhook delivery permanently fails.
+
+         Type a team member's name or email to search for suggestions. You can also enter any external email address, such as an on-call routing address for PagerDuty or OpsGenie.
+
+         Without a failure alert contact, Replicated notifies the subscription creator and all team admins by default.
+
    <!-- TODO: Add screenshot of delivery method selection -->
 
 1. Click **Create Notification**.

docs/vendor/event-notifications-manage.mdx

@@ -91,6 +91,7 @@ To edit a notification:
    - Add or update a custom subscription name to help identify the subscription
    - Add or remove event types, or modify filters on existing event types to broaden or narrow the scope
    - Change the delivery method or destination
+   - Update the **Failure alert contact** to change who receives webhook delivery failure notifications
    - Check or uncheck the **Enable this notification** checkbox to pause or unpause the notification
 
 1. Click **Save Changes**.