build: add new unit testing method

[diatrcz]

PR summary

Adds new way to create unit tests without using the root document for testing.

PR Checklist

General checklist

Please make sure that your PR fulfills the following requirements:

• The commit message follows the Angular Commit Message Guidelines.
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)
• Dependencies have been updated as needed
• .secrets.baseline has been updated as needed
• npm run update-utilities has been run if any files in packages/utilities/src have been updated

Checklist for adding a new validation rule:

• Added new validation rule definition (packages/ruleset/src/rules/*.js, index.js)
• If necessary, added new validation rule implementation (packages/ruleset/src/functions/*.js, updated index.js)
• Added new rule to default configuration (packages/ruleset/src/ibm-oas.js)
• Added tests for new rule (packages/ruleset/test/*.test.js)
• Added docs for new rule (docs/ibm-cloud-rules.md)
• Added scoring rubric entry for new rule (packages/validator/src/scoring-tool/rubric.js)

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 2 committers have signed the CLA.

✅ diatrcz
❌ Dan Hudlow

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[pyrooka]

LGTM!

[ibm-devx-sdk]

🎉 This PR is included in version 1.33.0 🎉

The release is available on npm package (@latest dist-tag)

Your semantic-release bot 📦🚀

[ibm-devx-sdk]

🎉 This PR is included in version 1.37.0 🎉

The release is available on npm package (@latest dist-tag)

Your semantic-release bot 📦🚀

[ibm-devx-sdk]

🎉 This PR is included in version 1.9.1 🎉

The release is available on npm package (@latest dist-tag)

Your semantic-release bot 📦🚀