curl --request GET \
  --url https://{defaultHost}/v5/app/notification_topics/{id} \
  --header 'Authorization: Bearer <token>'

{
  "app_id": "<string>",
  "created_at": 123,
  "name": "<string>",
  "description": "<string>",
  "notification_channel_identifiers": [
    "email"
  ],
  "status": "active",
  "topic_identifier": "<string>",
  "topic_type": "company",
  "visibility": "visible"
}