Remove blank output in PesterThrow.Tests.ps1

[fflaten]

PR Summary

This has been bugging me for a while 😄

PR Checklist

• PR has meaningful title
• Summary describes changes
• PR is ready to be merged
  • If not, use the arrow next to Create Pull Request to mark it as a draft. PR can be marked Ready for review when it's ready.
• Tests are added/update (if required)
• Documentation is updated/added (if required)

[nohwnd]

I was literally just looking at that :D