build API docker image from source

[wileyj]

default image for the api (unless a tagged version) is built only for amd64 arch.

propose updating hacknet to build the api from a branch/tag/commit similar to stacks-core so it's not dependent on any specific arch.

[BowTiedRadone]

The feature was pushed to this branch of my fork: https://github.com/BowTiedRadone/hacknet/tree/feat/build-api.