Create aspnet testing templates

[JunTaoLuo]

Following up to aspnet/Mvc#7710. We could consider shipping (either OOB or as part of the next SDK release) a template illustrating how to set up a test project for aspnet apps. The difference between this template and the normal test template is an additional reference <PackageReference Include="Microsoft.AspNetCore.App" /> and changing the SDK from Microsoft.NET.Sdk to Microsoft.NET.Sdk.Web.

[mkArtakMSFT]

@javiercn, how big of a work will this be?

[javiercn]

Around like 1 day of work give or take

[mkArtakMSFT]

@JunTaoLuo, @javiercn what about just having a sample? And not even worry about shipping it?

[javiercn]

@mkArtakMSFT We want a better experience. We already have a sample with the documentation. The out of the box experience must do better than that.