ci-playbook.yml: update the ui-bundle URL

Author: stephengold

src/site/ci-playbook.yml

@@ -12,7 +12,7 @@ content:
       start_path: docs/en
 ui:
   bundle:
-    url: https://github.com/stephengold/antora-ui-bundle/releases/download/v-sgold250101a/ui-bundle.zip
+    url: https://github.com/stephengold/antora-ui-bundle/releases/download/v-sgold260101a/ui-bundle.zip
     snapshot: true
 output:
   clean: true