file -> files in CI codecov step (#248)

Author: jishnub

.github/workflows/ci.yml

@@ -67,7 +67,7 @@ jobs:
       - uses: codecov/codecov-action@v5
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
-          file: lcov.info
+          files: lcov.info
   docs:
     name: Documentation
     runs-on: ubuntu-latest