title: DotNet alternative to spring boot @LocalServerPort for integration tests
body: <p>I am trying to test callback functionality of DotNet Core application. I have exposed controller that I would like to call within integration test.</p>
  <p>I have set up integration test using xUnit following <a href="https://docs.microsoft.com/en-us/aspnet/core/test/integration-tests?view=aspnetcore-3.1" rel="nofollow noreferrer">https://docs.microsoft.com/en-us/aspnet/core/test/integration-tests?view=aspnetcore-3.1</a>
  Within the test I am able to prepare client using WebApplicationFactory. It is possible to call required controller using this client.</p>
  <p>But my concern is how to call the controller from outside. In other words, is it exposed on some localhost port? I was not able to find such.
  It is not listening on 5000 (port defined in my appsettings). Nor it is listening on port 80 (default port).</p>
  <p>I would like to have something like spring boot @LocalServerPort and use it within test. Is there such possibility?</p>