Update codecov/codecov-action action to v4

Author: renovate[bot]

.github/workflows/ci.yml

@@ -20,4 +20,4 @@ jobs:
           check-latest: true
       - run: npm ci
       - run: npm test
-      - uses: codecov/codecov-action@v3
+      - uses: codecov/codecov-action@v4