Update Gherkin to v28

[gasparnagy]

🤔 What's changed?

The Gherkin dependency has been updated to v28 (from v19)

⚡️ What's your motivation?

There are some changes (mainly related to keyword translations). See https://github.com/cucumber/gherkin/blob/main/CHANGELOG.md

🏷️ What kind of change is this?

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

♻️ Anything particular you want feedback on?

📋 Checklist:

• I've changed the behaviour of the code
  • I have added/updated tests to cover my changes.
• Users should know about my change
  • I have added an entry to the "[vNext]" section of the CHANGELOG, linking to this pull request & included my GitHub handle to the release contributors list.

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This text was originally taken from the template of the Cucumber project, then edited by hand. You can modify the template here.

[Code-Grump]

Noting that I need to keep an eye on this for probable knock on in #200

[gasparnagy]

@Code-Grump No, I don't think so.

[gasparnagy]

@Code-Grump can you have a quick look and approve if ok?

[Code-Grump]

@Code-Grump can you have a quick look and approve if ok?

Can do.

[Code-Grump]

I checked through the Gherkin release notes and there doesn't seem to be any additions that we'd need to make code-changes for, so this PR is pleasingly minimal.

The simplifications to package references look good.