Update GitHub Actions workflow permissions for package publishing

[Copilot]

The workflow was failing to publish NuGet packages to GitHub Packages during pull requests because the default GITHUB_TOKEN lacked explicit package write permissions.

Changes

• Added workflow-level permissions block to .github/workflows/ci-cd.yml:

  permissions:
    contents: read
    packages: write

This grants the "Publish to Github packages" step the necessary permissions to push packages to nuget.pkg.github.com/sillsdev/index.json during PR builds.

Original prompt

Problem

The GitHub Actions workflow is failing when attempting to publish NuGet packages to GitHub Packages during pull requests. The step "Publish to Github packages" is encountering permission errors because the default GITHUB_TOKEN doesn't have explicit write permissions for packages.

Solution

Update the .github/workflows/ci-cd.yml file to include explicit permissions at the workflow level:

permissions:
  contents: read
  packages: write

Add this permissions block after the on: trigger section (around line 10, before the jobs: section).

Expected Outcome

After this change:

• The workflow will have explicit write permission for GitHub Packages
• The "Publish to Github packages" step will succeed during pull request builds
• NuGet packages will be successfully published to nuget.pkg.github.com/sillsdev/index.json

File to Modify

• .github/workflows/ci-cd.yml - Add the permissions block at the workflow level (between the on: section and jobs: section)

Reference

The specific step that needs these permissions:

- name: Publish to Github packages
  if: github.event_name == 'pull_request' && matrix.os == 'ubuntu-22.04'
  run: dotnet nuget push artifacts/*.nupkg -s https://nuget.pkg.github.com/sillsdev/index.json -k ${{secrets.GITHUB_TOKEN}} --skip-duplicate

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