No release history was found for the requested project
According to release updates.drupal.org, the module has release candidates for Drupal 7.x as per:


https://updates.drupal.org/release-history/registry_autoload/7.x


So try the following suggestions:


Make sure your IP is not blocked by going to https://updates.drupal.org/
Make sure your Drush recognise your Drupal root as 7.x (check drush status) and whether Drush can access the above endpoint by:

drush ev 'echo file_get_contents("https://updates.drupal.org/release-history/registry_autoload/7.x");


There could be a case that you are behind the firewall or corporate proxy, therefore the certificate could be not valid, so you'll have to configure your PHP's curl library either by importing the right certificate and mark it as trusted, ignoring it (not recommended) or use the non-secured connection to check for the new releases.