fix: 🐛 mockServer 更新失败提示

v2.0/mockServer/sdk/BaseDao.js

@@ -72,7 +72,7 @@ class BaseDao {
       options: options || {}
     })
     console.log(result)
-    let res = result.nModified > 0 ? 1 : 0
+    let res = result && result.nModified > 0 ? 1 : 0
     console.log(`update结果`, res)
     return res
   }