curl --request POST \
  --url https://api.bundleup.io/v1/sessions \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "integrationId": "<string>",
  "externalId": "<string>",
  "metadata": {},
  "redirectUri": "<string>"
}
'

{
  "expires_in": 123,
  "token": "<string>",
  "auth_url": "<string>",
  "external_id": "<string>"
}