Function jwtvault::utils::token::prepare_user_authentication_token

pub fn prepare_user_authentication_token<T: AsRef<[u8]>>(
    key: &PrivateKey, 
    iss: T, 
    reference: u64, 
    iat: i64, 
    nbf: i64, 
    exp: i64, 
    buffer: Option<HashMap<u64, Vec<u8>>>
) -> Result<String, Error>