upgrade actions-download-artifact version (#67)

Author: EliMoshkovich

.github/workflows/release.yaml

@@ -57,7 +57,7 @@ jobs:
         with:
           ref: gh-pages
       - name: download artifact
-        uses: actions/download-artifact@v2
+        uses: actions/download-artifact@v4
         id: download
         with:
           name: helm