Fix NuGet publish workflow for Linux runners

[Copilot]

Fix GitHub Actions workflow build failure

• Analyze workflow logs to identify the root cause
• Identify that nuget.exe cannot run on Linux (ubuntu-latest runner)
• Replace NuGet/setup-nuget action with dotnet nuget push command
• Address code review feedback - use env var for API key and add --skip-duplicate
• Apply reviewer suggestions - fix capitalization and quote API key variable
• Run final code review - no issues found
• Run security scan with CodeQL - no issues found

Original prompt

Fix the failing GitHub Actions workflow build
Analyze the workflow logs, identify the root cause of the failure, and implement a fix.
Job ID: 62735210084
Job URL: https://github.com/gfs/StreamRegex/actions/runs/21746995523/job/62735210084

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[Copilot]

Pull request overview

Updates the NuGet publishing GitHub Actions workflow to work on ubuntu-latest runners by switching from nuget.exe to the cross-platform dotnet nuget push.

Changes:

• Remove NuGet/setup-nuget and publish using dotnet nuget push
• Provide NuGet API key via an environment variable
• Add --skip-duplicate to make re-publishes idempotent

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[Copilot]

Pull request overview

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

Comments suppressed due to low confidence (1)

.github/workflows/publishnuget.yml:36

• dotnet pack is invoked without --configuration Release (defaults to Debug) and without --no-build, so it will rebuild and may produce/publish a Debug-config NuGet package. Consider using dotnet pack --no-build --configuration Release ... (and rely on the earlier Release build) to ensure the published package matches the intended configuration and to reduce CI time.

    - name: Build
      run: dotnet pack --no-restore StreamRegex.Extensions -o NuPkgs

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[Copilot]

The dotnet test step uses --no-restore but not --no-build or --configuration Release, so it will rebuild (defaulting to Debug) and won’t actually test the Release build produced in the previous step. Consider aligning with .github/workflows/test.yml by using dotnet test --no-build --configuration Release (and keep --verbosity normal if desired) to avoid redundant builds and ensure Release artifacts are validated.

This issue also appears on line 35 of the same file.

Suggested change

	run: dotnet test --no-restore --verbosity normal
	run: dotnet test --no-build --configuration Release --no-restore --verbosity normal

[gfs]

@copilot - this branch has already been merged, but implement these proposed changes as a new PR against main - also do a second pass of a code review for additional issues.