Expose UriProvider and refactor context usage

[davidjgoss]

🤔 What's changed?

Previously, we exposed <GherkinDocument/> publicly, but without providing a way to give it the UriContext it needs. That is now fixed with <UriProvider/>, which we use in <GherkinDocumentList/>.

Also, fixes #344 while we're here.

🏷️ What kind of change is this?

• 🏦 Refactoring/debt/DX (improvement to code design, tooling, etc. without changing behaviour)
• 🐛 Bug fix (non-breaking change which fixes a defect)
• ⚡ New feature (non-breaking change which adds new behaviour)

📋 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.

---

This text was originally generated from a template, then edited by hand. You can modify the template here.

[netlify]

✅ Deploy Preview for cucumber-react-preview ready!

Name	Link
🔨 Latest commit	0990a75
🔍 Latest deploy log	https://app.netlify.com/projects/cucumber-react-preview/deploys/6832f88a22c6f70008ee5912
😎 Deploy Preview	https://deploy-preview-386--cucumber-react-preview.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.