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

Author: renovate[bot]

.github/workflows/unit-tests.yml

@@ -54,7 +54,7 @@ jobs:
 
       - name: Upload coverage reports to Codecov
         if: ${{ !env.ACT }}
-        uses: codecov/codecov-action@671740ac38dd9b0130fbe1cec585b89eea48d3de # v5
+        uses: codecov/codecov-action@57e3a136b779b570ffcdbf80b3bdc90e7fab3de2 # v6
         with:
           env_vars: OS,PYTHON
           fail_ci_if_error: true