Makes no assumptions about the LibreOffice version. Simply links the .apt binary into the vendor directory.
To be used in conjuction with heroku-buildpack-apt
heroku buildpacks:add --index 1 https://github.com/heroku/heroku-buildpack-apt.git
heroku buildpacks:add --index 2 https://github.com/sumeetattree/heroku-buildpack-libreoffice.git
Create an Aptfile at the project root
:repo:deb http://http.us.debian.org/debian stretch main
libreoffice