Update subscription line item

curl --request PUT \
  --url https://api.cloud.flexprice.io/v1/subscriptions/lineitems/{id} \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '{
  "amount": 123,
  "billing_model": "FLAT_FEE",
  "effective_from": "<string>",
  "metadata": {},
  "tier_mode": "VOLUME",
  "tiers": [
    {
      "flat_amount": "<string>",
      "unit_amount": "<string>",
      "up_to": 123
    }
  ],
  "transform_quantity": {
    "divide_by": 123,
    "round": "<string>"
  }
}'

{
  "billing_period": "MONTHLY",
  "created_at": "<string>",
  "created_by": "<string>",
  "currency": "<string>",
  "customer_id": "<string>",
  "display_name": "<string>",
  "end_date": "<string>",
  "entity_id": "<string>",
  "entity_type": "plan",
  "environment_id": "<string>",
  "id": "<string>",
  "invoice_cadence": "ARREAR",
  "metadata": {},
  "meter_display_name": "<string>",
  "meter_id": "<string>",
  "plan_display_name": "<string>",
  "price_id": "<string>",
  "price_type": "USAGE",
  "price_unit": "<string>",
  "price_unit_id": "<string>",
  "quantity": 123,
  "start_date": "<string>",
  "status": "published",
  "subscription_id": "<string>",
  "tenant_id": "<string>",
  "trial_period": 123,
  "updated_at": "<string>",
  "updated_by": "<string>"
}