Status code 401 instead of 404 for clients not found in GET /clients/{id}

[antogyn]

Describe the bug

I updated hydra from 1.0.0 to 1.3.2 so I'm not sure when this bug was introduced, now calling /clients/{id} on the admin api with a non existing client id returns a 401 instead of a 404.

Reproducing the bug

Steps to reproduce the behavior:

# default configuration (admin port = 4445)
curl http://127.0.0.1:4445/clients/thisdoesnotexist

result:

{
  "error": "The request could not be authorized",
  "error_description": "The requested OAuth 2.0 client does not exist or you did not provide the necessary credentials",
  "status_code": 401,
  "request_id": ""
}

[antogyn]

Just realized this is a feature #1617

I think the documentation should be updated to remove 404 from possible errors

[aeneasr]

Correct, that should be indeed removed!