feat(App Engine) : Delete notification messages on based on some event

[moyrsd]

Background
In app engine, notification messages are messages which are only visible to the user. For example in github22 app when we use slash command /github help the githubbot app sends a message with all the things an user can do with the app.

Problem
Youtube Link
I wanted to implement this

• But,as you can see after pressing the button the notification message in not dissappearing. I am stuck here. I am trying to use this method, but getmessages doest consider bot messages as messages.

Solution
Create a method to delete notification messages based on triggers