Game SDK: VoiceManager.OnSettingsUpdate is not documented anywhere

[NathaanTFM]

VoiceManager.OnSettingsUpdate (on_settings_update event) is not documented anywhere and probably should be.

(Side note: I'd like to comment it but my english isn't good enough for that, so I'll let someone more qualified comment it)

struct IDiscordVoiceEvents {
    void (*on_settings_update)(void* event_data);
};

public event SettingsUpdateHandler OnSettingsUpdate;

[MonoPInvokeCallback]
private static void OnSettingsUpdateImpl(IntPtr ptr)
{
    GCHandle h = GCHandle.FromIntPtr(ptr);
    Discord d = (Discord)h.Target;
    if (d.VoiceManagerInstance.OnSettingsUpdate != null)
    {
        d.VoiceManagerInstance.OnSettingsUpdate.Invoke();
    }
}