curl --request GET \
  --url https://api.hubapi.com/settings/v3/users/teams \
  --header 'private-app: <api-key>'

{
  "results": [
    {
      "id": "100",
      "name": "Test Team",
      "userIds": [
        "123"
      ],
      "secondaryUserIds": [
        "124"
      ]
    }
  ]
}