Reproducible build for binary signing

[wileyj]

Similar to what other projects do to verify a binary, we should create a reproducible build process to democratize the release process more.
The first step is providing a process that others can use to verify a build artifact, and later the ci release process may use this signed artifact to perform a "release" build.

Opening this issue as the first step into investigating if this would be feasible (or even a good idea for stacks).

https://guix.gnu.org/manual/devel/en/guix.html
https://guix.gnu.org/en/blog/2020/reproducible-computations-with-guix/

and using bitcoin as inspiration:
https://gist.github.com/eriknylund/a58d7587f785881eee0aea10bba60546
https://github.com/bitcoin/bitcoin/blob/master/doc/release-process.md#building
https://github.com/bitcoin-core/guix.sigs
https://github.com/bitcoin-core/bitcoin-detached-sigs

another interesting idea to look into is to timestamp the build artifacts: https://opentimestamps.org/