Revert "Avoid scanning anonymous classes (#3150)"

[mpkorstanje]

⚡️ What's your motivation?

This reverts commit 3f27ff4 from #3150 which broke Cucumber Scala which can implicitly define anonymous classes. They're an error, but still an error that should be detected. See for details cucumber/cucumber-jvm-scala#425.

🏷️ What kind of change is this?

• 🐛 Bug fix (non-breaking change which fixes a defect)

📋 Checklist:

• I agree to respect and uphold the Cucumber Community Code of Conduct
• I've changed the behaviour of the code
  • I have added/updated tests to cover my changes.
• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
• Users should know about my change
  • I have added an entry to the "Unreleased" section of the CHANGELOG, linking to this pull request.