I've investigated the bug a little further. Since the url is opened with https protocol it tries automatically to use the https_proxy environment variable which is not set on my system, only http_proxy. I've set the https_proxy variable and tried to run "ubuntu-bug -p apport" again and I've received a different error, "HTTP Error 501: Not Implemented".
-- apport fails to use environment proxy configuration https://launchpad.net/bugs/94130 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs