List scheduled emails

{
  "schedules": [
    {
      "id": "string",
      "template": {
        "id": "string",
        "messageType": "string",
        "studyKey": "string",
        "defaultLanguage": "string",
        "headerOverrides": {},
        "translations": [
          {}
        ]
      },
      "type": "string",
      "studyKey": "string",
      "condition": {},
      "nextTime": 0,
      "period": 0,
      "label": "string",
      "until": 0
    }
  ]
}

{
  "error": "string"
}

{
  "error": "string"
}

{
  "error": "string"
}