Good question! These are the exact same versions of Facter that are bundled with the nightly puppet-agent builds, so no additional steps are needed if you're already using nightly agent builds.
Additionally, as most of you know, Facter 4 is also available as facter-ng on the puppet6 stream. Previously we used to manually bump the facter-ng version which led to Facter 4 being outdated at times in the puppet6 nightly build. This process has been automated and both puppet-agent 6 and 7 builds should come with the latest nightly versions of Facter 4.