Provide conflicting worker configuration ID when a user tries to create the same one

Bastien Abadie
2022-07-18T09:22:50Z

When an API user tries to create the exact same configuration payload, the backend should return a 400 with a detailed id and name field in the payload.

Having both ID & name is important to allow the frontend to display them to the user.

refs https://gitlab.com/arkindex/requests/-/issues/728