List focus groups

curl --request GET \
  --url https://app.mavera.io/api/v1/focus-groups \
  --header 'Authorization: Bearer <token>'

{
  "object": "list",
  "data": [
    {
      "id": "<string>",
      "object": "focus_group",
      "status": "<string>",
      "created_at": 123,
      "updated_at": 123,
      "name": "<string>",
      "sample_size": 123,
      "personas_count": 123,
      "questions_count": 123,
      "error": "<string>"
    }
  ],
  "has_more": true,
  "next_cursor": "<string>"
}