chore: Explicitely enforce Chromatic build node version

[engfragui]

Short description

When working on #757, I noticed en error in the "Publish to Chromatic" build:

Error: error:0308010C:digital envelope routines::unsupported

Based on "the internet", it seems like this is due to fact that that build is running on Node v18, even though we're not (yet) intentionally supporting it in Reactist.

It actually started failing even before this PR, when I merged my previous PR. See this build: https://github.com/Doist/reactist/actions/runs/4224761740/jobs/7336138735

The best solution here seems to be to ensure that, before running the Chromatic publish step, we actually select the intended Node version, instead of relying on the default Node version that's brought in by ubuntu-latest, which apparently recently switched from Node 16 to Node 18.

I actually "took" this fix from todoist-web (cypress build): https://github.com/Doist/todoist-web/blob/main/.github/workflows/check-cypress-automation.yml#L92-L97

PR Checklist

• Added tests for bugs / new features
• Updated docs (storybooks, readme)
• Executed npm run validate and made sure no errors / warnings were shown
• Described changes in CHANGELOG.md
• Bumped version in package.json and package-lock.json (npm --no-git-tag-version version <major|minor|patch>) ref
• Updated all static build artifacts (npm run build-all)
• Reviewed and approved Chromatic visual regression tests in CI

Versioning

[gnapse]

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