Get custom questions

curl --request GET \
  --url https://api.letsway.com/v1/brands/{brandId}/experiences/{experienceId}/custom-questions

{
  "items": [
    {
      "id": "qst-123",
      "prompt": "What is your favorite color?",
      "fieldType": "single_select",
      "config": {
        "maxLength": 100
      },
      "options": [
        {
          "key": "color",
          "value": "blue"
        }
      ]
    }
  ]
}