Update codecov/codecov-action action to v3 (#216)

Co-authored-by: Renovate Bot <[email protected]>

Author: renovate[bot]

.github/workflows/unit-tests.yml

@@ -24,7 +24,7 @@ jobs:
       - name: jest
         run: npm run test --coverage
       - name: Send coverage to codecov
-        uses: codecov/codecov-action@v2
+        uses: codecov/codecov-action@v3
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           flags: unittests