UpdateCampaignConditionRequest(UpdateCampaignConditionRequest)

A condition holds ONE typed value, in its own column — gender, country_id,
city_id or item_id — chosen by the condition's type. There is no values
array: the earlier version of this request asked for one, so the update wrote
a column that does not exist and quietly changed nothing.

{
    "gender_value": "string",
    "country_id": 0,
    "city_id": 0,
    "item_id": 0
}