Replace secret retrieval with az-artifact-authenticate step in CI workflow

[Copilot]

This PR updates the CI pipeline to use the shared az-artifact-authenticate step from workleap/wl-reusable-workflows for Azure DevOps artifact feed authentication, replacing the previous manual secret retrieval approach.

Changes Made

CI Workflow (.github/workflows/ci.yml)

• Replaced the Get gsoft-nuget-feed-ado-pat secret step with the az-artifact-authenticate action
• Removed the separate actions/setup-dotnet@v4 step (now included in az-artifact-authenticate)
• Simplified environment variables by removing NUGET_API_KEY (authentication now handled via VSS_NUGET_ACCESSTOKEN)
• Configured the action to use variables: ${{ toJSON(vars) }} for cleaner parameter passing

Build Script (Build.ps1)

• Added support for VSS_NUGET_ACCESSTOKEN authentication alongside existing NUGET_API_KEY
• Uses "az-api-key" as the API key when authenticating with Azure DevOps tokens
• Maintains backward compatibility with existing authentication methods

Authentication Flow

The new authentication logic follows this precedence:

1. NUGET_API_KEY on Linux (existing behavior)
2. VSS_NUGET_ACCESSTOKEN on any platform (new Azure Artifacts authentication)
3. No push if neither is available

Benefits

• Simplified CI configuration by consolidating authentication steps and using variables object
• Improved security through Azure CLI-based authentication
• Enhanced cross-platform support (VSS_NUGET_ACCESSTOKEN works on any OS)
• Maintained full backward compatibility

The az-artifact-authenticate step handles Azure CLI login, .NET setup, and credential provider installation automatically, reducing the CI workflow complexity while providing more robust authentication.

Fixes #120.

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Pull Request Overview

This PR modernizes the CI pipeline's Azure DevOps artifact feed authentication by replacing manual secret retrieval with a dedicated reusable workflow action. The change simplifies the CI configuration while maintaining backward compatibility and improving cross-platform support.

• Replaces manual secret retrieval step with az-artifact-authenticate action
• Updates build script to support VSS_NUGET_ACCESSTOKEN authentication alongside existing methods
• Removes redundant .NET setup step and simplifies environment variable configuration

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
.github/workflows/ci.yml	Replaces secret retrieval and .NET setup with consolidated az-artifact-authenticate action
Build.ps1	Adds support for VSS_NUGET_ACCESSTOKEN authentication with az-api-key

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