because previous commits didn't leave this file alone but rather made
lots of changes into it and then subsequently removed it.

will add subsequent changes here to make tests trigger on each PR
however this is a good starting point

- cargo check
- cargo clippy
- cargo fmt
- cargo test

for the upstream code just prefix them with underscore to minimize
differences, for creditcoin/ just remove them

because fmt and clippy appear to be slightly different from version to
version and we'd like to have consistency regardless of how or where
this is built

because .env.example has been removed in
ca51756