Issue Description

Building or just restoring fails with an error.

dotnet-install: The resource at legacy link 'https://dotnetbuilds.azureedge.net/public/Runtime/3.1.0/dotnet-osx-arm64.3.1.0.tar.gz' is not available.
dotnet_install: Error: Could not find `.NET Core Runtime` with version = 3.1.0
dotnet_install: Error: Refer to: https://aka.ms/dotnet-os-lifecycle for information on .NET Core support

Steps to Reproduce

1. Clone the repo to an Apple Silicon machine. (Commit 659a296 is where the issue is introduced.)
2. Execute ./build.sh --restore

Expected Behavior

Restore should complete without errors.

Actual Behavior

Restore fails -- which also blocks builds.

Analysis

There is no arm64 version of runtime 3.10. PR #7826 changed global.json and introduced a dependency on runtime 3.10.

Versions & Configurations

macOS Monterey 12.4; Apple M1 Pro (arm64)