Remove MediaPlayer async restart hack when using VLC 4.0
Between each media playback, the MediaPlayer is deleted asynchronously from a coroutine and a new MediaPlayer is created to handle the next media.
This was done in VLC 3.0 to fix some freeze with few inputs.
It is not needed anymore in VLC 4.0 since the new vlc_player is now taking care of stopping the media asynchronously.
The MediaPlayer still need to be restarted when changing (some) user options.