Update to 3.5.2 and .net core 2.1

MediaBrowser.Controller/Entities/TagExtensions.cs

@@ -1,35 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using MediaBrowser.Model.Extensions;
-
-namespace MediaBrowser.Controller.Entities
-{
-    public static class TagExtensions
-    {
-        public static void AddTag(this BaseItem item, string name)
-        {
-            if (string.IsNullOrWhiteSpace(name))
-            {
-                throw new ArgumentNullException("name");
-            }
-
-            var current = item.Tags;
-
-            if (!current.Contains(name, StringComparer.OrdinalIgnoreCase))
-            {
-                if (current.Length == 0)
-                {
-                    item.Tags = new[] { name };
-                }
-                else
-                {
-                    var list = current.ToArray(current.Length + 1);
-                    list[list.Length - 1] = name;
-
-                    item.Tags = list;
-                }
-            }
-        }
-    }
-}