ci: use Gitea-compatible accessibility artifacts

.gitea/workflows/quality.yml

@@ -53,7 +53,7 @@ jobs:
           npm run test:photo
           npm run test:sleek
       - name: Upload accessibility screenshots
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v3
         if: always()
         with:
           name: a11y-screenshots