cicd: check for formatting and clippy in ci

.github/workflows/build.yml

@@ -12,6 +12,8 @@ jobs:
     - uses: actions/checkout@v2
     - name: Install Rust toolchain
       uses: dtolnay/rust-toolchain@stable
+    - name: Formatting & Lints
+      run: cargo fmt -- --check && cargo clippy -- -D warnings
     - name: Build
       run: cargo build --verbose
     - name: Run tests