Remove __v from GET /api/registry/users

[david-rocca]

Currently there is a __v being returned:

Example:
{
"UUID": "20000000-0000-4000-8000-000000000022",
"username": "patriciawilliams@beat_10.com",
"name": {
"first": "Patricia",
"middle": "W",
"last": "Williams",
"suffix": "Jr."
},
"status": "active",
"created": "2021-05-11T15:07:20.674Z",
"last_updated": "2021-05-11T15:07:20.674Z",
"__v": 0
}

__v needs to be removed.