Deprecated method util._extend

[Morta1]

Description

Please explain the changes you made here.

• Node v22+ is now alerting about deprecation of util._extend and suggests using Object.assign instead.

Checklist

• Format code according to the existing code style (run npm run lint:check -- CHANGED_FILES and fix problems in changed code)
• Create tests which fail without the change (if possible)
• Make all tests (unit and integration) pass (npm run test:unit and npm run test:integration)
• Extend the types in index.d.ts file (if necessary)
• Extend the README / documentation and ensure is properly displayed (if necessary)
• Provide JIRA issue id (if possible) or GitHub issue id in commit message

[github-actions]

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[Morta1]

I have read the CLA Document and I hereby sign the CLA