Create managed guardrail config

curl --request POST \
  --url https://api.example.com/api/v1/guardrails/ \
  --header 'Content-Type: application/json' \
  --data '
{
  "name": "<string>",
  "guardrail": {
    "banned_words": [
      "<string>"
    ],
    "config_id": "ban_list",
    "api_key": "",
    "reject_message": ""
  }
}
'

{
  "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "name": "<string>",
  "guardrail": {
    "banned_words": [
      "<string>"
    ],
    "config_id": "ban_list",
    "api_key": "",
    "reject_message": ""
  },
  "created_at": "2023-11-07T05:31:56Z",
  "updated_at": "2023-11-07T05:31:56Z",
  "agent_count": 0
}