chore(deps): update codecov/codecov-action action to v6 (#66)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/tox-tests.yml

@@ -90,7 +90,7 @@ jobs:
       - name: Run Tox
         run: tox -e py3
       - name: Upload coverage to Codecov
-        uses: codecov/codecov-action@v5
+        uses: codecov/codecov-action@v6
         env:
           CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
         with: