Modified dependencies versions

The new version of Ghostscript (upgraded in the previous commit) has
changed the PDF interpreter
(https://www.ghostscript.com/blog/pdfi.html). This breaks the code by
causing fonts not to be embedded.

This change passes a command line flag to Ghostcript to tell it to use
the original interpreter. While we will need to upgrade the interpreter
too, this is best done as its own piece of work when we're not also
changing the base image and other dependencies.