Place empty file in dist directory.

Author: owo

.github/workflows/wheels.yml

@@ -57,7 +57,7 @@ jobs:
         env:
           CIBW_PROJECT_REQUIRES_PYTHON: "3.9"
 
-        run: pip install --upgrade pip && pip install build && python -m build --sdist --outdir dist && touch empty.txt
+        run: pip install --upgrade pip && pip install build && python -m build --sdist --outdir dist && touch dist/empty.txt
 
       - uses: actions/upload-artifact@v4
         with: