UI: Added option to check for updates in the background

src/Ryujinx/Utilities/Configuration/UI/UpdaterType.cs

@@ -0,0 +1,13 @@
+using Ryujinx.Common.Utilities;
+using System.Text.Json.Serialization;
+
+namespace Ryujinx.Ava.Utilities.Configuration.UI
+{
+    [JsonConverter(typeof(TypedStringEnumConverter<UpdaterType>))]
+    public enum UpdaterType
+    {
+        Off,
+        PromptAtStartup,
+        CheckInBackground
+    }
+}