title: Using 'UseMvc' to configure MVC is not supported while using Endpoint Routing
body: <p>I had an Asp.Net core 2.2 project. </p>
  
  <p>Recently, I changed the version from .net core 2.2 to .net core 3.0 Preview 8. After this change I see this warning message: </p>
  
  <blockquote>
    <p>using 'UseMvc' to configure MVC is not supported while using Endpoint
    Routing. To continue using 'UseMvc', please set
    'MvcOptions.EnableEndpointRouting = false' inside 'ConfigureServices'.</p>
  </blockquote>
  
  <p>I understand that by setting <code>EnableEndpointRouting</code> to false I can solve the issue, but I need to know what is the proper way to solve it and why Endpoint Routing does not need <code>UseMvc()</code> function.</p>