[Bug] 修复 rest_request UDF 报错 “No content to map to Obeject due to end of input”的问题.Fix the error of rest_request UDF "No content to map to Obeject due to end of input".

[ZhengshuaiPENG]

当使用 rest 数据源时，采用下面的语法可以调通获取数据，api 是可以返回的

load Rest.`$worklog_list_url` 
 where `config.connect-timeout`="10s"
  and `config.method`="POST"
  and `header.content-type`="application/json"
  and `header.Authorization`='''Bearer $acc_ko'''
  and `body`='''{ 
   "ids": $ids
 } '''
as worklog_list1;

如果换成下面的 rest_request 的udf 来进行多次 api 调用时，返回的内容会报错 No content to map to Obeject due to end of input

 select  rest_request(
     "$worklog_list_url","POST", -- url/method
     map("ids",ids), -- params
     map("Content-Type" , "application/json", "Authorization", "Bearer $acc_ko"), -- headers
     map() -- config
 )  as resp from id_arrays_by_buckets as worklog_list1;

[hellozepp]

#1709 fixd it.