Use documented syntax for GitHub action conditional

[MarkEWaite]

Use documented syntax for GitHub action conditional

The GitHub Action documentation shows that ${{ }} needs to wrap the term of the conditional

Testing done

Used in many other repositories. Refer to git plugin and git client plugin for examples.

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests that demonstrate the feature works or the issue is fixed