Include SendAsync in the ITestServer abstraction

Author: mkArtakMSFT

src/Hosting/TestHost/src/ITestServer.cs

@@ -4,6 +4,7 @@
 using System.Net.Http;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Hosting.Server;
+using Microsoft.AspNetCore.Http;
 
 namespace Microsoft.AspNetCore.TestHost;
 
@@ -26,6 +27,12 @@ public interface ITestServer : IServer
     /// <summary>
     /// Creates a new <see cref="HttpClient"/> for processing HTTP requests against the test server.
     /// </summary>
-    /// <returns></returns>
+    /// <returns>An HttpClient instance configured to work with the current test server.</returns>
     HttpClient CreateClient();
+
+    /// <summary>
+    /// Creates, configures, sends, and returns a <see cref="HttpContext"/>. This completes as soon as the response is started.
+    /// </summary>
+    /// <returns>The HttpContext associated with the sent request.</returns>
+    Task<HttpContext> SendAsync(Action<HttpContext> configureContext, CancellationToken cancellationToken = default);
 }

src/Hosting/TestHost/src/PublicAPI.Unshipped.txt

@@ -4,4 +4,5 @@ Microsoft.AspNetCore.TestHost.ITestServer.CreateClient() -> System.Net.Http.Http
 Microsoft.AspNetCore.TestHost.ITestServer.CreateHandler() -> System.Net.Http.HttpMessageHandler!
 Microsoft.AspNetCore.TestHost.ITestServer.Host.get -> Microsoft.AspNetCore.Hosting.IWebHost!
 *REMOVED*static Microsoft.AspNetCore.TestHost.HostBuilderTestServerExtensions.GetTestServer(this Microsoft.Extensions.Hosting.IHost! host) -> Microsoft.AspNetCore.TestHost.TestServer!
+Microsoft.AspNetCore.TestHost.ITestServer.SendAsync(System.Action<Microsoft.AspNetCore.Http.HttpContext!>! configureContext, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) -> System.Threading.Tasks.Task<Microsoft.AspNetCore.Http.HttpContext!>!
 static Microsoft.AspNetCore.TestHost.HostBuilderTestServerExtensions.GetTestServer(this Microsoft.Extensions.Hosting.IHost! host) -> Microsoft.AspNetCore.TestHost.ITestServer!