Replace #region syntax with // <snippet_name> format in sample files according to copilot-instructions.md

Co-authored-by: wadepickett <[email protected]>

Author: Copilot

aspnetcore/security/authentication/cookie/samples/3.x/CookieSample/Startup.cs

@@ -24,7 +24,7 @@ public void ConfigureServices(IServiceCollection services)
             services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
         }
 
-        #region snippet_policy
+        // <snippet_policy>
         public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
         {
             if (env.IsDevelopment())
@@ -59,6 +59,6 @@ public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
                 endpoints.MapRazorPages();
             });
         }
-        #endregion
+        // </snippet_policy>
     }
 }

aspnetcore/security/authentication/cookie/samples/6.x/CookieSample/Program.cs

@@ -72,7 +72,7 @@
 app.Run();
 #endregion
 #elif POLICY
-#region snippet_policy
+// <snippet_policy>
 using Microsoft.AspNetCore.Authentication.Cookies;
 
 var builder = WebApplication.CreateBuilder(args);
@@ -117,7 +117,7 @@
 app.MapDefaultControllerRoute();
 
 app.Run();
-#endregion
+// </snippet_policy>
 #elif CC
 #region snippet_cc
 using Microsoft.AspNetCore.Authentication.Cookies;