ci(tests): codecov/codecov-action@v4

See also:
- https://github.com/codecov/codecov-action/releases/tag/v4.0.0
- https://github.com/codecov/codecov-action/releases/tag/v4.0.1

Author: tony

.github/workflows/tests.yml

@@ -78,7 +78,7 @@ jobs:
           tmux -V
           poetry run py.test --cov=./ --cov-report=xml
 
-      - uses: codecov/codecov-action@v3
+      - uses: codecov/codecov-action@v4
         with:
           token: ${{ secrets.CODECOV_TOKEN }}