Low Code Python CDK: Support nested authentication.

[michael-airbyte]

The current low code builder does not support nesting an access token, or the ability for the connector to be able to fetch it's own token.

The Tiktok Global Shop API requires x-tts-access-token to be present. Currently this can only be done manually, and cannot be nested into the request itself.

Manually adding a valid token, and sending a POST request you get back a refresh token back.

{
  "code":0,
  "message":"success",
  "data": {
    "access_token":"xxx",
    "access_token_expire_in": "time",
    "refresh_token":"yyy,"
    "refresh_token_expire_in": "time",
  }
}

This could be passed along back to the the connector, and update the endpoint with the new token.