Aspnetcore.docs: Target Framework section should mention that .NET Framework is only an option for ASP.NET Core 2.1

[Pilchie]

You can no longer target .NET Framework with with recent versions of ASP.NET Core (3.0 and 3.1). This section should be updated to reflect that.

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Document Details

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• ID: 1133d6d1-7801-654c-2b7c-dad2bb342501
• Version Independent ID: a7ccce22-f905-06f4-8847-b9eeaf534e1f
• Content: Migrate from ASP.NET to ASP.NET Core
• Content Source: aspnetcore/migration/proper-to-2x/index.md
• Product: aspnet-core
• Technology: aspnetcore-migration
• GitHub Login: @isaac2004
• Microsoft Alias: scaddie

[Rick-Anderson]

Related dotnet/docs#16571

[scottaddie]

@Rick-Anderson This entire doc needs to be updated from 2.2 to 3.1.

[Rick-Anderson]

@scottaddie thanks for catching that. Your reward is I assigned this to you :)