audio supports to fire an event upon its playing state

User Story

1. As an application developer, I want to add an event listener when the end of the media is reached so that I can perform my specific business logic e.g. trigger the next audio or show a special message.
2. As an application developer, I want to add an event listener for playing state change, e.g. ended, pause, play, so that I can add my application logic to those event listeners.

original case: https://potix.freshdesk.com/a/tickets/12072

Details

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/audio#events