add ret msg and fix plateNos is nil

liuxiaolong

2020-07-09 844bd2c00b417982ba504d0e2fef8a605ad8c808

 service/carService_test.go

@@ -1,11 +1,9 @@
package service

import (
   "fmt"
   "testing"
)

func TestCarService_Statistic(t *testing.T) {
   parkList := getHikParkList()
   fmt.Println("parkList:", parkList)

}