Change to `MediaPlayer` API to allow waiting for the player to be in a ready state.
This is needed in order to perform some tasks (e.g. read the media duration, seek) after changing the media file.
* Show voice message preview player progress
* Update screenshots
* Fix test
* Some nits over mediaplayer stuff
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Co-authored-by: ElementBot <benoitm+elementbot@element.io>
Co-authored-by: Marco Romano <marcor@element.io>