make a few classes static

src/Microsoft.Tye.Core/ApplicationYamlWriter.cs

@@ -9,7 +9,7 @@ using YamlDotNet.RepresentationModel;
 
 namespace Microsoft.Tye
 {
-    public sealed class ApplicationYamlWriter
+    public static class ApplicationYamlWriter
     {
         public static Task WriteAsync(OutputContext output, StreamWriter writer, ApplicationBuilder application)
         {

src/Microsoft.Tye.Hosting.Diagnostics/DiagnosticsCollector.cs

@@ -848,7 +848,7 @@ namespace Microsoft.Tye.Hosting.Diagnostics
             public static readonly string HttpFlavorKey = "http.flavor";
         }
 
-        internal sealed class LoggingEventSource
+        internal static class LoggingEventSource
         {
             /// <summary>
             /// This is public from an EventSource consumer point of view, but since these definitions

src/tye/InitHost.cs

@@ -1,10 +1,10 @@
 using System.IO;
 using Microsoft.Tye.ConfigModel;
-using Microsoft.Tye.Serialization;
+using Microsoft.Tye.Serialization;
 
 namespace Microsoft.Tye
 {
-    public class InitHost
+    public static class InitHost
     {
         public static string CreateTyeFile(FileInfo? path, bool force)
         {