Update output for Discovery and Filter

[fflaten]

PR Summary

• Removes file-specific discovery message from Detailed view. This is still available as Discovery debug-messages in Diagnostic
• Output number of tests to be executed.
• Removes redundant and noisy active tag filter debugmessages (covered in initial discovery-output in Detailed + Diagnostic), see before-image here Debugging generated tests takes for ever due to the output of filter commands #1746 (comment)
• Fix runtime configuration leak when using advanced configuration with Invoke-Pester -Configuration ...

Example of output after PR:

Diagnostic:

Fix #1552
Fix #1746
Fix #1972

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]

Perfect, thanks!