API key auth is not supported

[james-kessler]

A collection with API key auth set (on a collection or endpoint) will fail to parse with an error message of

data did not match any variant of untagged enum PostmanCollection.

An example of API key auth looks like

"auth": {
            "type": "apikey",
            "apikey": [
                {
                    "key": "value",
                    "value": "bar",
                    "type": "string"
                },
                {
                    "key": "key",
                    "value": "foo",
                    "type": "string"
                }
            ]
        },

Currently AuthType does not contain an entry for apikey, nor Auth

Example request