fix AggregationResult struct

[shijianzhiwai]

Sometimes value is an object.

{
  "aggregationResults":[
            {
                "type":"number",
                "value":10
            },
            {
                "type":"date",
                "value":{
                    "type":"datetimerange",
                    "start_date":"2021-03-27",
                    "start_time":"00:00",
                    "end_date":"2021-04-04",
                    "end_time":"00:00",
                    "time_zone":"America/Los_Angeles"
                }
            },
            {
                "type":"number",
                "value":1595.5
            },
            {
                "type":"number",
                "value":3191
            }
        ]
}

[kjk]

thanks!