feat: no guava - java 21 version (Math.clamp)

[SimonVerhoeven]

What's changed?

Introduces a new No guava - Java 21 recipe which extends the No Guava - Java 11 recipe, and also contains a new recipe which replaces the Guava - constrainToRange with the new Java 21 clamp method.

What's your motivation?

To help people make use of core Java features.

Anything in particular you'd like reviewers to focus on?

Anyone you would like to review specifically?

Have you considered any alternatives or workarounds?

Any additional context

Checklist

• I've added unit tests to cover both positive and negative cases
• I've added the license header to any new files through ./gradlew licenseFormat
• I've used the IntelliJ IDEA auto-formatter on affected files

[timtebeek]

Looking good! Thanks for spotting and fixing these.

[timtebeek]

The tests could be slightly more descriptive if we add a return value for the methods, just to show that hasn't changed.