Add codecov_token env variable to upload coverage report

Author: lucianopaz

.github/workflows/test.yml

@@ -259,7 +259,8 @@ jobs:
           path: coverage
 
       - name: Upload coverage to Codecov
-        uses: codecov/codecov-action@v3
+        uses: codecov/codecov-action@v4
         with:
           directory: ./coverage/
           fail_ci_if_error: true
+          token: ${{ secrets.CODECOV_TOKEN }}