[Spike] Migrate backend to Prisma

In card #274 @cvanem did some excellent research on outlining what it would take to migrate from the graphcool-fraemwork to prisma. This card is to track spiking out an implementation of this work i.e. getting a hacky version of the site running on prisma somewhere instead of on the graphcool framework (possibly by doing things like disabling auth).

Start with the research in card #274 and the existing backend configuration; the issue does not name specific files, tests, or entry points. A spike is complete when a hacky version of the site runs on Prisma instead of the graphcool framework, possibly with authentication disabled.

Written by the indexing model from the issue text.