修改PD配置报错：tiup ctl:v6.5.0 pd config placement save --in=rules.json

是不是因为少了最后那个isolation_level？

{
  "group_id": "pd",
  "id": "default",
  "start_key": "",
  "end_key": "",
  "role": "voter",
  "count": 3,
  "location_labels": ["zone", "rack", "host"],
  "isolation_level": ""
}