[QUESTION]fastjson 1.2.83->2.0.53 含有Date类型的JSONObject调用toString()方法怎么可以保持一致

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*询问有关本项目的使用和其他方面的相关问题。*

我在fastjson的1.2.83版本和2.0.53分别执行了以下代码：

```
@Getter
@Setter
public class Test{
private Date lastLoginTime;
}
```

```
@SneakyThrows
public static void main(String[] args) {
JSONObject results = new JSONObject();
Test test = new Test();
test.setLastLoginTime(DateUtils.parseDate("2024-09-20 14:54:35","yyyy-MM-dd HH:mm:ss"));
results.put("test", test);
System.out.println(results.toString());
}
```

fastjson1.x的返回:
`{"test":{"lastLoginTime":1726815275000}}`

fastjson2.x的返回：
`{"test":{"lastLoginTime":"2024-09-20 14:54:35"}}`

请问上述返回，我要怎么做才能和fastjson1.x返回一致？

The reproduction uses the Test class, DateUtils.parseDate, JSONObject.put, and JSONObject.toString() across fastjson 1.2.83 and 2.0.53. Start by checking the date serialization behavior and configuration options for both versions. Done means documenting or verifying how fastjson2 can produce the epoch-millisecond output shown for fastjson 1.x.

Written by the indexing model from the issue text.