CI: Use Node 18, 20

[olleolleolle]

🤔 What's changed?

Fix #219 by changing the build matrix to use newer versions.

⚡️ What's your motivation?

In order to keep up with Node versions that are current, and also, to conserve CI resources, use two Node.js versions. The two that are shown on the Node.js website.

I will also update the other Workflow.

🏷️ What kind of change is this?

• :bank: Refactoring/debt/DX (improvement to code design, tooling, documentation etc. without changing behaviour)

♻️ Anything particular you want feedback on?

n/a

📋 Checklist:

• [x] 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.