Fix release syntax & remove nix (#86)

Author: epk

.github/workflows/release.yml

@@ -33,5 +33,5 @@ jobs:
     - uses: Shopify/upload-to-release@master
       with:
         name: shadowenv-${{ matrix.target }}
-        path: target/{{ matrix.target }}/release/shadowenv
+        path: target/${{ matrix.target }}/release/shadowenv
         repo-token: ${{ secrets.GITHUB_TOKEN }}

CONTRIBUTING.md

@@ -1,20 +1,7 @@
 # Releasing Shadowenv
 
 1. Bump the version in `Cargo.toml`
-1. In `default.nix` replace the `cargoSha256` value with "0000000000000000000000000000000000000000000000000000"
-1. Run `nix build` and replace `cargoSha256` with the expected hash (which might not have changed after all)
 1. Commit with the message "bump version to x.y.z".
 1. Tag the commit as x.y.z (no leading 'v')
 1. Push the commit and the tag
 1. Create a new release at https://github.com/Shopify/shadowenv/releases
-
-## (shopify-internal) releasing to `dev`:
-
-1. `dev clone dev`, fetch master, etc.
-1. Run `dev prefetch-shopify-repo shadowenv <version>` to get nix hash
-1. In the  `shadowenv` section of `src/nixpkgs-overlay/default.nix`
-   1. Update `version`
-   1. Update `src > sha256` with the nix hash from step #2 above
-   1. Update `cargoDeps > outputHash` with the `cargoHash256` value from Shadowenv's `default.nix` if needed
-1. `dev test-nix-package shadowenv`
-1. Commit, put, PR, you know the drill.