when type asserting fails here, err is reassigned with nil and the
default block of the switch prints out <nil> in the error message. This
makes debugging a configuration or access token issue difficult
The particular error this surfaces is:
Response: {
"error": "unauthorized_client",
"error_description": "Client is unauthorized to retrieve access tokens using this method, or client not authorized for any of the scopes requested."
}
Signed-off-by: Josh Bielick <jbielick@gmail.com>
