Restore cache before running cargo fmt

It appears cargo fmt also downloads the git dependencies which takes quite a while. The cache should contain a copy of the cloned repo, so restoring the cache early should speed things up.

.github/workflows/build.yml

@@ -23,15 +23,15 @@ jobs:
       - name: Install rustfmt
         run: rustup component add rustfmt --toolchain stable-x86_64-apple-darwin
         if: ${{ matrix.os == 'macos-latest' }}
-      - name: Check formatting
-        run: cargo fmt --all -- --check
       - uses: actions/cache@v2
         with:
           path: |
             ~/.cargo/registry
             ~/.cargo/git
             target
-          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+          key: ${{ runner.os }}-rust-cargo-${{ hashFiles('**/Cargo.lock') }}
+      - name: Check formatting
+        run: cargo fmt --all -- --check
       - name: Build
         run: cargo build --verbose
       - name: Run tests