Update default globs to work with Pytest-BDD conventions

[aslakhellesoy]

🤔 What's changed?

The globs for finding step definitions

⚡️ What's your motivation?

Work out of the box with pytest-bdd conventions. See https://github.com/cucumber/language-service/pull/84#issuecomment-1229978912

🏷️ What kind of change is this?

• :zap: New feature (non-breaking change which adds new behaviour)

📋 Checklist:

• [x] I agree to respect and uphold the Cucumber Community Code of Conduct
• [x] 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.
• [x] Users should know about my change
  • [x] I have added an entry to the "Unreleased" section of the CHANGELOG, linking to this pull request.