Conflicting boost versions on Ubuntu Focal (due to alternatives)

When building gds* on top of ldas-tools-* on Ubuntu 20.04 (focal), I'm running into version issues with libboost*-dev: https://git.ligo.org/gds/gds/-/issues/106

@ed-maros can you find out whether this is a gds* problem, or a ldas-tools-* one? Patches to debian/control are welcome.