Fix some compilation warnings (#1010)

* Fixe some summary warning

* Fixed more warning

* Uniformed example projects code

* Uniformed test projects code

* Fix OperatingSystems enum and GenericType summaries

tests/KubernetesClient.Classic.Tests/SimpleTests.cs

@@ -1,9 +1,9 @@
+using k8s.Models;
 using System.IO;
 using System.Net;
 using System.Net.Sockets;
 using System.Threading.Tasks;
 using Xunit;
-using k8s.Models;
 
 namespace k8s.tests;
 
@@ -12,7 +12,7 @@ public class BasicTests
     // TODO: fail to setup asp.net core 6 on net48
     private class DummyHttpServer : System.IDisposable
     {
-        private TcpListener server;
+        private readonly TcpListener server;
         private readonly Task loop;
         private volatile bool running = false;