Currently we can add webhooks for organizations but not for users. This PR adds the latter. You can access it from the current users settings. ![grafik](https://user-images.githubusercontent.com/1666336/197391408-15dfdc23-b476-4d0c-82f7-9bc9b065988f.png)
* Fix validate() function to handle errors in embedded anon structs * Implement webhook branch filter See #2025, #3998.