onError method
Called when an exception was occurred during the request.
Implementation
@override
void onError(DioException err, ErrorInterceptorHandler handler) async {
/// If unauthorized (401), call the onUnauthorized callback and remove token.
if (err.response?.statusCode == 401 && onUnauthorized != null) {
onUnauthorized!();
await LocalStorageService.removeToken();
}
/// Forward the error.
handler.next(err);
}