Install .NET LTS instead of STS

[adamralph]

Proposed Changes

1. Switch to the LTS .NET release channel to allow .NET 8 to be installed. This is required because some new C# language features, such as collection expressions, cause dotnet format in .NET 7 to get confused, and it reports false problems.

STS restricts the version the latest Standard Term Support release, which is currently 7.0.404:

% ./dotnet-install.sh --dry-run --channel STS
dotnet-install: Payload URLs:
dotnet-install: URL #0 - aka.ms: https://dotnetcli.azureedge.net/dotnet/Sdk/7.0.404/dotnet-sdk-7.0.404-osx-arm64.tar.gz

LTS allows latest Long Term Support release, which is currently 8.0.100:

% ./dotnet-install.sh --dry-run --channel LTS
dotnet-install: Payload URLs:
dotnet-install: URL #0 - aka.ms: https://dotnetcli.azureedge.net/dotnet/Sdk/8.0.100/dotnet-sdk-8.0.100-osx-arm64.tar.gz

Unfortunately, there is no way to say "STS or LTS, whichever is newer":

  -c,--channel <CHANNEL>         Download from the channel specified, Defaults to `LTS`.
      -Channel
          Possible values:
          - STS - the most recent Standard Term Support release
          - LTS - the most recent Long Term Support release
          - 2-part version in a format A.B - represents a specific release
              examples: 2.0; 1.0
          - 3-part version in a format A.B.Cxx - represents a specific SDK release
              examples: 5.0.1xx, 5.0.2xx.
              Supported since 5.0 release
          Warning: Value 'Current' is deprecated for the Channel parameter. Use 'STS' instead.
          Note: The version parameter overrides the channel parameter when any version other than 'latest' is used.

Another option is to state the actual version:

% ./dotnet-install.sh --dry-run --channel 8.0 
dotnet-install: Payload URLs:
dotnet-install: URL #0 - aka.ms: https://dotnetcli.azureedge.net/dotnet/Sdk/8.0.100/dotnet-sdk-8.0.100-osx-arm64.tar.gz

Readiness Checklist

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Pull request author tasks

• I included all the needed documentation for this change.
• I provided the necessary tests.
• I squashed all the commits into a single commit.
• I followed the Conventional Commit v1.0.0 spec.

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• Label as breaking if this change breaks compatibility with the previous released version.
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[ferrarimarco]

Hi @adamralph ! Thanks for this PR.

Until we put automated dependency updates in place for .NET, this seems like a good change.

[ferrarimarco]

Minor changes:

• Can you refactor the commit heading to say: feat: install .NET LTS instead of STS
• Can you add a description of the change in the commit body? Basically a summary of what you explained in the PR.

Thanks a lot!

[adamralph]

Minor changes:

• Can you refactor the commit heading to say: feat: install .NET LTS instead of STS
• Can you add a description of the change in the commit body? Basically a summary of what you explained in the PR.

Thanks a lot!

@ferrarimarco done