apt_security_updates fact misses some security updates in Ubuntu in 2.3.0

The apt_security_updates fact misses some security updates on Ubuntu when it is present, with puppetlabs-apt 2.3.0. On my test systems it always returns 0, although other systems may return non-zero values depending on their available updates.

This seems to be related to ebf9d9f6a629dc69973cad6092080f36ec5af1d6, which switched away from using apt-check to using apt-get -s upgrade and regular expressions. It fails to match security updates with the following output:

Inst vim-common [2:7.4.1689-3ubuntu1.1] (2:7.4.1689-3ubuntu1.2 Ubuntu:16.04/xenial-security, Ubuntu:16.04/xenial-updates [amd64])

The regex / Ubuntu[^\s]+-security / would match the line if Ubuntu:16.04/xenial-security was the only source which had a newer package. However, since the package is also available from ubuntu:16.04/xenial-updates, there is a comma after "-security" instead of a space.