Implement SpotifyGame details

src/Discord.Net.Core/Entities/Activities/SpotifyGame.cs

@@ -1,3 +1,4 @@
+using System.Collections.Generic;
 using System.Diagnostics;
 
 namespace Discord
@@ -11,6 +12,7 @@ namespace Discord
         public string TrackAlbum { get; internal set; }
         public string SyncId { get; internal set; }
         public string SessionId { get; internal set; }
+        public string[] Artists { get; internal set; }
 
         public override string ToString() => Name;
         private string DebuggerDisplay => $"{Name} (Spotify)";

src/Discord.Net.WebSocket/Extensions/EntityExtensions.cs

@@ -7,8 +7,15 @@ namespace Discord.WebSocket
             // Spotify Game
             if (model.SyncId.IsSpecified)
             {
-                return new SpotifyGame()
+                var assets = model.Assets.GetValueOrDefault()?.ToEntity();
+                return new SpotifyGame
                 {
+                    Name = model.Name,
+                    SessionId = model.SessionId.GetValueOrDefault(),
+                    SyncId = model.SyncId.Value,
+                    TrackAlbum = assets?[1]?.Text,
+                    TrackTitle = model.Details.GetValueOrDefault(),
+                    Artists = model.State.GetValueOrDefault()?.Split(';')
                 };
             }