fix request pass-through aws channels can't test

common.GetRequestBody(c) read bod is null

controller/channel-test.go

@@ -332,7 +332,7 @@ func testChannel(channel *model.Channel, testModel string, endpointType string)
 	}
 
 	requestBody := bytes.NewBuffer(jsonData)
-	c.Request.Body = io.NopCloser(requestBody)
+	c.Request.Body = io.NopCloser(bytes.NewBuffer(jsonData))
 	resp, err := adaptor.DoRequest(c, info, requestBody)
 	if err != nil {
 		return testResult{