Calling Stop() on a live stream results in Paused state - iOS

## 🐛 Bug Report

When Playing a live stream (mp3), calling `MediaManager.Current.Stop()` puts media manager into `MediaPlayerState.Paused` state.

### Expected behavior

Media manager should end up in the `MediaPlayerState.Stopped` state.

### Reproduction steps

```
CrossMediaManager.Current.Play( /* live stream mp3 */ );

// .. after the stream has started:
CrossMediaManager.Current.Stop();
```

### Configuration

**Version:** 1.0.8

**Platform:**
- [x] :iphone: iOS
- [ ] :robot: Android
- [ ] :checkered_flag: WPF
- [ ] :earth_americas: UWP
- [ ] :apple: MacOS
- [ ] :tv: tvOS
- [ ] :monkey: Xamarin.Forms

Start by reproducing the issue on iOS with the CrossMediaManager.Current.Play and Stop calls shown in the report, then trace the resulting MediaPlayerState transition. Done means stopping a live MP3 stream leaves the media manager in MediaPlayerState.Stopped rather than Paused.

Written by the indexing model from the issue text.