`dotnet tool install -a arm64` fails on linux-arm64

Describe the bug

dotnet tool install --global <tool-name> --arch arm64 fails reporting that the RID linux-arm64 is invalid.

To Reproduce

1. Create Amazon Linux 2 ARM 64 Instance
2. Install dotnet 6
3. run dotnet tool install --global dotnet-sonarscanner --arch arm64

Exceptions (if any)

Unhandled exception: System.AggregateException: One or more errors occurred. (The runtime identifier linux-arm64 is invalid. Valid runtime identifiers are: win-x64 win-arm64 osx-x64 osx-arm64.)
 ---> Microsoft.DotNet.Cli.Utils.GracefulException: The runtime identifier linux-arm64 is invalid. Valid runtime identifiers are: win-x64 win-arm64 osx-x64 osx-arm64.
   at Microsoft.DotNet.ShellShim.ShellShimTemplateFinder.ResolveAppHostSourceDirectoryAsync(String archOption, NuGetFramework targetFramework, Architecture arch)
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task`1.GetResultCore(Boolean waitCompletionNotification)
   at System.Threading.Tasks.Task`1.get_Result()
   at Microsoft.DotNet.Tools.Tool.Install.ToolInstallGlobalOrToolPathCommand.Execute()
   at Microsoft.DotNet.Tools.Tool.Install.ToolInstallCommand.Execute()
   at Microsoft.DotNet.Cli.ToolInstallCommandParser.<>c.<ConstructCommand>b__14_0(ParseResult parseResult)
   at Microsoft.DotNet.Cli.ParseResultCommandHandler.Invoke(InvocationContext context)
   at System.CommandLine.Invocation.InvocationPipeline.<>c__DisplayClass4_0.<<BuildInvocationChain>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass12_0.<<UseHelp>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c.<<UseSuggestDirective>b__18_0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass16_0.<<UseParseDirective>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass8_0.<<UseExceptionHandler>b__0>d.MoveNext()

Further technical details

dotnet --info

dotnet --info
.NET SDK (reflecting any global.json):
 Version:   6.0.302
 Commit:    c857713418

Runtime Environment:
 OS Name:     amzn
 OS Version:  2
 OS Platform: Linux
 RID:         linux-arm64
 Base Path:   /home/bambooagent/dotnet/sdk/6.0.302/

global.json file:
  Not found

Host:
  Version:      6.0.7
  Architecture: arm64
  Commit:       0ec02c8c96

.NET SDKs installed:
  3.1.422 [/home/bambooagent/dotnet/sdk]
  6.0.302 [/home/bambooagent/dotnet/sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 3.1.28 [/home/bambooagent/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.7 [/home/bambooagent/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 3.1.28 [/home/bambooagent/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.7 [/home/bambooagent/dotnet/shared/Microsoft.NETCore.App]

Download .NET:
  https://aka.ms/dotnet-download

Learn about .NET Runtimes and SDKs:
  https://aka.ms/dotnet/runtimes-sdk-info

• The IDE (VS / VS Code/ VS4Mac) you’re running on, and its version

[dsplaisted]

I’m not sure why the list of RuntimeIdentifiers is hardcoded there. Looking at the code it looks like you can’t install global tools at all on Linux, though I may be missing something.

Ideally I think the same data that goes in to Microsoft.NETCoreSdk.BundledVersions.props about what RIDs are available for apphosts should be used to drive the tool install too.

[cn-ml]

I get the same output when cross-building AMD64 / ARM64 Docker images on either host machine architecture, but only when I supply the architecture flag to docker tool install.