Use full callouts response in upstream request

callout.json

{
	"name": "request-callout",
	"config": {
		"callouts": [
			{
				"name": "c1",
				"request": {
					"url": "https://mocki.io/v1/3b51613b-a7e0-44bf-803a-35f6939e55f3",
					"method": "GET"
				},
				"response": {
					"body": {
						"decode": true
					}
				}
			},
			{
				"name": "c2",
				"request": {
					"url": "https://mocki.io/v1/c5232232-fb9f-4f2d-9835-6b08e2ae005c",
					"method": "GET"
				},
				"response": {
					"body": {
						"decode": true
					}
				}
			}
		],
	   "upstream": {
		  "by_lua": "local callouts = kong.ctx.shared.callouts; kong.service.request.set_body({ ['c1-request'] = callouts.c1.response.body, ['c2-request'] = callouts.c2.response.body }, 'application/json')"
		}
	}
}