Migrate from Commons Lang to native Java Platform functionality

[timja]

No need to depend on a third-party library here when the Java Platform provides this functionality natively.

Part of the effort to remove Commons Lang 2 from Jenkins core — jenkinsci/jenkins#16404,
jenkinsci/jenkins#26105. Commons Lang 2 is EOL and carries an unfixed advisory
(GHSA-j288-q9x7-2f5v).

NotImplementedException becomes UnsupportedOperationException. Commons Lang 2's
NotImplementedException extends UnsupportedOperationException, so anything catching the supertype
still behaves identically — and this avoids pulling in Lang 3 for a single throw.

Testing done

mvn -B -ntp clean verify on Java 21 / macOS. The build fails on a pre-existing SpotBugs finding
(a write to the static KinesisSink.streamName from an instance method, in code this PR does not touch)
— unmodified master fails with exactly the same single finding.
The ban-commons-lang-2 enforcer rule was left disabled because it needs parent POM
6.2116.v7501b_67dc517 or newer; bumping the parent from 4.78 was out of scope here.

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests that demonstrate the feature works or the issue is fixed

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🤖 This pull request was generated with AI assistance (Claude Code) as part of a bulk migration
across Jenkins plugins. If anything here looks wrong, please comment on this PR or contact
@parameter.