Allow triggering of test webhooks via the API
Problem to solve
There used to be a way to trigger a test on webhook through a call to the GUI on
This can't be done now because of CRSF protection and a way to trigger a project's hook from API does not seems to exists.
On some setup, calling the webhooks directly may be a no-go at network level and, as a bonus, Gitlab provide also a level of authentication.
Add an API way to trigger a project's webhooks next to other hooks operations (https://docs.gitlab.com/ee/api/projects.html#hooks).
What does success look like, and how can we measure that?
Project's webhook can be triggered through an API call and we could get the result as JSON.