Update codecov/codecov-action action to v5.4.0

Author: renovate[bot]

.github/workflows/flutter.yml

@@ -43,7 +43,7 @@ jobs:
         with:
           name: failures
           path: "**/failures/"
-      - uses: codecov/codecov-action@13ce06bfc6bbe3ecf90edbbf1bc32fe5978ca1d3 # v5.3.1
+      - uses: codecov/codecov-action@0565863a31f2c772f9f0395002a31e3f06189574 # v5.4.0
         with:
           fail_ci_if_error: true
           token: ${{ secrets.CODECOV_TOKEN }}