Fixed incorrect version of an action

Author: dmladek

.github/workflows/deploy.yml

@@ -25,7 +25,7 @@ jobs:
         run: npm run build #  → this calls `vite build --mode production` (as defined in package.json)
 
       - name: Upload dist as artifact
-        uses: actions/upload-pages-artifact@v4
+        uses: actions/upload-pages-artifact@v3
         with:
           name: github-pages-artifact
           path: '.dist'