Create or update a promotion

curl --request POST \
     --url https://app.amberflo.io/payments/pricing/amberflo/account-pricing/promotions/time_limited_tiered_relative_product_discount \
     --header 'accept: application/json' \
     --header 'content-type: application/json' \
     --data '{
     "id": "",
     "type": "time_limited_tiered_relative_product_discount",
     "promotionName": ""
     }'