curl --request GET \
  --url https://api.example.com/cabinet/promo/group-discounts \
  --header 'Authorization: Bearer <token>'

{
  "group_name": "<string>",
  "server_discount_percent": 0,
  "traffic_discount_percent": 0,
  "device_discount_percent": 0,
  "period_discounts": {}
}