Update codecov/codecov-action action to v6

Author: renovate[bot]

.github/workflows/coverage.yml

@@ -30,7 +30,7 @@ jobs:
         pip install pytest-cov
         pytest --cov=./ovos_microphone_plugin_files --cov-report=xml
     - name: Upload coverage to Codecov
-      uses: codecov/codecov-action@v3
+      uses: codecov/codecov-action@v6
       with:
         token: ${{ secrets.CODECOV_TOKEN }}
         directory: ./coverage/reports/