📝 Publish release note for 3.21.0

[dubzzz]

Description

Release note, nothing more!

Checklist — Don't delete this checklist and make sure you do the following before opening the PR

• The name of my PR follows gitmoji specification
• My PR references one of several related issues (if any)
  • New features or breaking changes must come with an associated Issue or Discussion
  • My PR does not add any new dependency without an associated Issue or Discussion
• My PR includes bumps details, please run yarn bump and flag the impacts properly
• My PR adds relevant tests and they would have failed without my PR (when applicable)

Advanced

• Category: 📝 Add or update documentation
• Impacts: None

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@fast-check/examples	Configuration

[github-actions]

👋 A preview of the new documentation is available at: http://66b7297ffdff58fe7b3d4420--dubzzz-fast-check.netlify.app