Can't receive Webhook: meeting.participant_joined. (The app is not released yet)

Description
I read this article and it seems that only after the app is released, then I can receive the meeting.participant_joined from the user (who has installed the app).

Question
if so, how can I test it(meeting.participant_joined)?

Hi @jobyrao
If your app has not been published yet, you can test it with the development credentials by sharing the app to an user under your account using the authorization URL