Create an audience

curl --request POST \
  --url https://your_a2_service/audiences \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "id": "<string>",
  "alt_id": {},
  "created_at": "2023-11-07T05:31:56Z",
  "id_type": "account_id",
  "properties": {},
  "updated_at": "2023-11-07T05:31:56Z"
}
'

{
  "id": "<string>",
  "alt_id": {},
  "created_at": "2023-11-07T05:31:56Z",
  "id_type": "account_id",
  "properties": {},
  "updated_at": "2023-11-07T05:31:56Z"
}