M.A.App should be version-less

[Rick-Anderson]

The templates don't generate a version. This sample shouldn't.
See this PR to backout changes

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Document Details

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• ID: cabe9331-b438-fabe-18ca-15f752ec6778
• Version Independent ID: 3294609f-b881-1fec-de04-2021b48de489
• Content: Microsoft.AspNetCore.App metapackage for ASP.NET Core 2.1 and later
• Content Source: aspnetcore/fundamentals/metapackage-app.md
• Product: aspnet-core
• GitHub Login: @Rick-Anderson
• Microsoft Alias: riande

[guardrex]

@Rick-Anderson @scottaddie So was it as of the 2.1.3 release that they went back to implicit versioning? If so, then let me know if you'd like me to run back thru the samps and drop the versions from App package references.

[Rick-Anderson]

I'll find out next Tuesday when @natemcmaster returns from VAC. Can you remind me then? I'm guessing yes.

[guardrex]

@Rick-Anderson Reminder to ask Nate about adding back the versions to our App package refs.

[natemcmaster]

After lots of discussion and experimentation, we are going to stick with original design -- versionless PackageReference is the recommended way to use Microsoft.AspNetCore.App. We should update our docs and guidance to match this recommendation.

Just FYI - we implemented and tested alternatives ways to reference the Microsoft.AspNetCore.App shared framework. While these might have been accepted if we had done them in the first place, we did not feel the benefits of switching approaches outweighed the costs. This was especially true as we began to design 3.0. In 3.0, we plan to rework the way shared frameworks are referenced in projects. Rather than introducing more churn, we're going to make some improvements in the 2.2 SDK for using the versionless PackageReference (see dotnet/sdk#2533), and will focus our efforts on making 3.0 better.