Restored a change in the public API.shipped file

Author: mkArtakMSFT

src/Mvc/Mvc.Testing/src/PublicAPI.Shipped.txt

@@ -16,6 +16,7 @@ Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory<TEntryPoint>.CreateDefaul
 Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory<TEntryPoint>.CreateDefaultClient(System.Uri! baseAddress, params System.Net.Http.DelegatingHandler![]! handlers) -> System.Net.Http.HttpClient!
 Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory<TEntryPoint>.Dispose() -> void
 Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory<TEntryPoint>.Factories.get -> System.Collections.Generic.IReadOnlyList<Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory<TEntryPoint!>!>!
+Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory<TEntryPoint>.Server.get -> Microsoft.AspNetCore.TestHost.TestServer!
 Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory<TEntryPoint>.WebApplicationFactory() -> void
 Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory<TEntryPoint>.WithWebHostBuilder(System.Action<Microsoft.AspNetCore.Hosting.IWebHostBuilder!>! configuration) -> Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactory<TEntryPoint!>!
 Microsoft.AspNetCore.Mvc.Testing.WebApplicationFactoryClientOptions