Updating to TelegramBotFramework 16.0.2

ATTENTION: UserIds will no longer be "int", instead it has to be of the long datatype
- updating DeviceSession methods for new datatype
- updating LinkReplaceTest class example
- adding .NET 5 as target framework

TelegramBotBaseTest/Tests/Groups/LinkReplaceTest.cs

@@ -12,7 +12,7 @@ namespace TelegramBotBaseTest.Tests.Groups
     public class LinkReplaceTest : TelegramBotBase.Form.GroupForm
     {
 
-        Dictionary<int, int> Counter { get; set; } = new Dictionary<int, int>();
+        Dictionary<long, int> Counter { get; set; } = new Dictionary<long, int>();
 
         private const int Maximum = 3;