Missing %d for http `code`

[rbpasker]

https://github.com/ivanahuckova/avocado_monitoring/blob/3bdcee8f99a21f3fe6a39d70b64ac0b7d962e090/avocado_monitoring.ino#L75

Serial.printf("Loki [HTTPS] POST... Code: %d \n", httpCode);