Incorrect information for <aspnetcore21

[GeorgeAlexandria]

The section #add-a-controller describe how to add a new controller for <.aspnetcore21 (in the issue scope younger versions are not interested), it just use ApiControllerAttribute to decorate controller that allow controller responds to web API requests. Besides, ApiControllerAttribute was introduced at aspnetcore21 (https://docs.microsoft.com/ru-ru/dotnet/api/microsoft.aspnetcore.mvc.apicontrollerattribute?view=aspnetcore-2.2#applies-to) and it cannot be used in [.aspnetcore10;.aspnetcore20], so this describes is incorrect for <.aspnetcore21.

If I miss something, please let me know about it.

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Document Details

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• ID: 583ae3e7-5915-f22b-e54c-6c100cf2a7da
• Version Independent ID: 95f2549e-29f9-e31a-b4d0-432b971643ff
• Content: Tutorial: Create a web API with ASP.NET Core
• Content Source: aspnetcore/tutorials/first-web-api.md
• Product: aspnet-core
• Technology: aspnetcore-tutorials
• GitHub Login: @Rick-Anderson
• Microsoft Alias: riande

[Rick-Anderson]

@GeorgeAlexandria thanks for the feedback. We should probably remove the version selector for 1..0 to 2.0 since we don't support those versions.

cc @scottaddie