Changes to List Agents

added the optional property items/items/avg_call_duration to the response with the 200 status

added the optional property items/items/calls_today to the response with the 200 status

added the optional property items/items/conversion_rate to the response with the 200 status

added the required property items/items/status to the response with the 200 status

deleted the query request parameter campaign_id

removed the optional property items/items/campaign_id from the response with the 200 status

removed the optional property items/items/campaign_name from the response with the 200 status

added the new optional query request parameter use_case_id

added the optional property items/items/use_case_id to the response with the 200 status

added the optional property items/items/use_case_name to the response with the 200 status