DELETE /v1/sellers/{id}/asks/{ask_id}
Cancel a resting ask.
Auth: X-Seller-API-Key.
Response: 204 on success, 404 if the ask is unknown.
curl -s -X DELETE http://127.0.0.1:8080/v1/sellers/SELLER_ID/asks/ASK_ID \
-H "X-Seller-API-Key: sk-seller"