Fix release build

MediaBrowser.Controller/Entities/PersonInfo.cs

@@ -42,7 +42,7 @@ namespace MediaBrowser.Controller.Entities
         /// <value>The sort order.</value>
         public int? SortOrder { get; set; }
 
-        public string? ImageUrl { get; set; }
+        public string ImageUrl { get; set; }
 
         public Dictionary<string, string> ProviderIds { get; set; }