Update actions/upload-artifact to v4

Author: salty-horse

.github/workflows/wheel.yml

@@ -41,7 +41,7 @@ jobs:
         run: pytest --verbose test_snappy.py
 
       - name: Archive sdist
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         with:
           name: wheels
           path: dist/python-snappy*.tar.gz