Get management user

{
  "user": {
    "id": "string",
    "sub": "string",
    "email": "user@example.com",
    "username": "string",
    "provider": "string",
    "imageUrl": "http://example.com",
    "isAdmin": true,
    "lastLoginAt": "2019-08-24T14:15:22Z",
    "createdAt": "2019-08-24T14:15:22Z"
  }
}

{
  "error": "string"
}

{
  "error": "string"
}

{
  "error": "string"
}