Add product pricing

curl --request POST \
  --url https://services.commercengine.dev/api/v1/x2yh61zw4k/admin/catalog/products/{product-id}/pricing \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '[
  {
    "customer_group_id": "<string>",
    "cost_price": 123,
    "listing_price": 123,
    "selling_price": 123,
    "min_order_quantity": 123,
    "max_order_quantity": 123,
    "incremental_quantity": 123,
    "tax_type": "<string>",
    "tax_rate": 123
  }
]'

{
  "message": "<string>",
  "success": true,
  "content": {
    "pricing": [
      {
        "id": 123,
        "customer_group_id": "<string>",
        "cost_price": 123,
        "listing_price": 123,
        "selling_price": 123,
        "min_order_quantity": 123,
        "max_order_quantity": 123,
        "incremental_quantity": 123,
        "tax_type": "<string>",
        "tax_rate": 123
      }
    ]
  }
}