Updated SettingJson

Changed from object to string, as it was to difficult to handle any data
field in the value.

FreeTubeSync/Model/Json/SettingJson.cs

@@ -6,5 +6,5 @@ namespace FreeTubeSync.Model.Json;
 public class SettingJson
 {
     public string _id { get; set; } = string.Empty;
-    public object value { get; set; } 
+    public string value { get; set; } 
 }