PR Summary

This pull request includes several changes across multiple pipeline templates to streamline the use of .NET Core SDK and improve the bootstrap process. The most important changes involve replacing Start-PSBootstrap with UseDotNet@2 tasks and updating the Start-PSBootstrap command to use the -Scenario parameter.

Streamlining the use of .NET Core SDK:

• .pipelines/templates/compliance/apiscan.yml: Replaced Start-PSBootstrap with UseDotNet@2 task for using the .NET Core SDK.
• .pipelines/templates/linux.yml: Added UseDotNet@2 task for using the .NET Core SDK. [1] [2]
• .pipelines/templates/nupkg.yml: Added UseDotNet@2 task and removed Start-PSBootstrap.
• .pipelines/templates/release-validate-fxdpackages.yml: Replaced Start-PSBootstrap with UseDotNet@2 task for using the .NET Core SDK.
• .pipelines/templates/testartifacts.yml: Replaced Start-PSBootstrap with UseDotNet@2 task for using the .NET Core SDK. [1] [2]

Updating Start-PSBootstrap command:

• .pipelines/templates/linux-package-build.yml: Updated Start-PSBootstrap to use -Scenario Package.
• .pipelines/templates/mac-package-build.yml: Updated Start-PSBootstrap to use -Scenario Package.
• .pipelines/templates/windows-hosted-build.yml: Updated Start-PSBootstrap to use -Scenario Package and removed redundant calls. [1] [2] [3] [4]
• .pipelines/templates/windows-package-build.yml: Updated Start-PSBootstrap to use -Scenario Package. [1] [2]
• .vsts-ci/linux/templates/packaging.yml: Updated Start-PSBootstrap to use -Scenario Package.

These changes aim to standardize the usage of .NET Core SDK and improve the maintainability of the pipeline scripts.

PR Context

PR Checklist

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• User-facing changes
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  • Documentation needed
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• Tooling
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    • Impact on PowerShell Editor Services which is used in the PowerShell extension for VSCode
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    • Impact on EditorSyntax (which provides syntax highlighting with in VSCode, GitHub, and many other editors).
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