title: how to configure webhook activity?
body: <p>I wonder what the webhook activity used for. this is my first webhook activity ,configured as below screenshot it failed when I debug this activity as below, if I want to update key vault through this activity, what should I configure?</p>
  <p><a href="https://i.stack.imgur.com/1oAYD.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1oAYD.png" alt="enter image description here" /></a></p>