re-enable codecov (#48)

Author: davidhewitt

.github/workflows/ci.yml

@@ -70,15 +70,15 @@ jobs:
     - id: cache-rust
       uses: Swatinem/rust-cache@v2
 
-    - run: cargo test --all-features
-#    - uses: taiki-e/install-action@cargo-llvm-cov
-#
-#    - run: cargo llvm-cov --all-features --codecov --output-path codecov.json
-#
-#    - uses: codecov/codecov-action@v3
-#      with:
-#        files: codecov.json
-#        env_vars: RUST_VERSION
+    - uses: taiki-e/install-action@cargo-llvm-cov
+
+    - run: cargo llvm-cov --all-features --codecov --output-path codecov.json
+
+    - uses: codecov/codecov-action@v3
+      with:
+        token: ${{ secrets.CODECOV_TOKEN }}
+        files: codecov.json
+        env_vars: RUST_VERSION
 
   # https://github.com/marketplace/actions/alls-green#why used for branch protection checks
   check: