chore(dependencies): update codecov/codecov-action action to v6 (#174)

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

Author: renovate[bot]

.github/workflows/test.yml

@@ -26,4 +26,4 @@ jobs:
           CFLAGS: "-DCYTHON_TRACE=1"
           BENCODER_LINETRACE: 1
       - run: python -m pytest --cov=bencoder --cov-report=xml .
-      - uses: codecov/codecov-action@v5
+      - uses: codecov/codecov-action@v6