backport #28213 This PR will fix some missed checks for private repositories' data on web routes and API routes.
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)