Revert "fix possible bans from Pavel Durov"

This reverts commit 1460cb0a75.

Core/Extensions/UserExtension.cs

@@ -1,17 +1,12 @@
-using System;
-using System.Text;
+using System.Text;
 using Telegram.Bot.Types;
 
 namespace Kruzya.TelegramBot.Core.Extensions;
 
 public static class UserExtension
 {
-    [Obsolete("Insecure method, currently replaced to dummy text 'Chat Member'")]
     public static string ToHtml(this User user, bool byUsername = false)
     {
-        return "Пользователь";
-
-        /**
         var text = new StringBuilder();
         text.Append($"<a href=\"tg://user?id={user.Id}\">");
            
@@ -24,7 +19,6 @@ public static class UserExtension
             text.Append($"{user.FirstName} {user.LastName}".Trim().HtmlEncode());
         }
         return text.Append("</a>").ToString();
-        */
     }
 
     public static string ToLog(this User user)