Update actions/upload-pages-artifact@v3

Author: xyzjesper

.github/workflows/doc.yml

@@ -42,7 +42,7 @@ jobs:
         uses: actions/configure-pages@v3
 
       - name: Upload artifact
-        uses: actions/upload-pages-artifact@v2
+        uses: actions/upload-pages-artifact@v3
         with:
           # Upload entire repository
           path: './docs'