(fix) Upgrade codecov-action version

Author: aarmoa

.github/workflows/run-tests.yml

@@ -40,6 +40,6 @@ jobs:
           poetry run pytest --cov --cov-report=xml
 
       - name: Upload coverage to Codecov
-        uses: codecov/codecov-action@v3
+        uses: codecov/codecov-action@v4
         with:
           env_vars: OS,PYTHON