In the default preseed template as ships with the foreman, the "enable puppetlabs repo" feature is broken.

d-i apt-setup/local1/repository string \
http://apt.puppetlabs.com/ <%= @host.operatingsystem.release_name %> main
d-i apt-setup/local1/comment string Puppetlabs packages
d-i apt-setup/local1/key string http://apt.puppetlabs.com/pubkey.gpg

This doesn't work because the scripts start at index 0, so it never adds these repos.

I'll have a PR for this in a moment