On Debian based systems (confirmed on 8 and 9 currently) where lsb-release is not installed (this happens on netinst builds done with no net, if someone wants to replicate), the lsb-release package is not installed.
When it is not installed, lsb related facter facts are not present. This has some unusual action at a distance, eg the puppet/apt forge module explodes in a way that wasn't obvious until examining the source.
Depending on how you look at it, this is technically not a Puppet bug. However it is affecting Puppet and the fix is minor and best done via Puppet agent packaging.
I feel the best fix would be to make sure that lsb-release is a dependency in the puppet-agent package on Debian based systems.
No, I cannot just add a "lsb-release" package requirement in the manifest. This was my first thought. Unfortunately the missing package means the manifest can't be compiled due to missing facts generally, thus the request the packaging pull this in as a dependency.