asToken method Null safety
As an AuthToken.
Implementation
AuthToken asToken() {
return AuthToken()
..accessToken = accessToken
..refreshToken = refreshToken
..issueDate = issueDate
..expirationDate = expirationDate
..type = type
..resourceOwnerIdentifier = resourceOwner!.id
..scopes = scope?.split(" ").map((s) => AuthScope(s)).toList()
..clientID = client.id;
}