Issue downloading from Drupal.org when URL is https

When Drush is attempting to Download files from drupal.org and the target URL is using https rather than http it seems unable to Download the file.

This affected me on my local machine but not Chris on his local machine when running the same make file (standard Cambridge profile make file). Changing the target URL to use http rather than https resolves the problem so we need to change the URL in the profile at some point.