use newer version of codecov action

Author: thvdveld

.github/workflows/rust.yml

@@ -61,7 +61,9 @@ jobs:
         cargo llvm-cov --no-report
         cargo llvm-cov report --lcov --output-path lcov.info
     - name: Upload coverage to Codecov
-      uses: codecov/codecov-action@v3
+      uses: codecov/codecov-action@v4.0.1
       with:
+        token: ${{ secrets.CODECOV_TOKEN }}
         files: lcov.info
         fail_ci_if_error: false
+        slug: thvdveld/dot15d4