chore(workflows): update Node.js version to 22 in CI configurations

[andyma-star]

Summary

• Update GitHub Actions workflow in .github/workflows/test.yml to run tests on Node.js 22 (from 20).
• Update GitHub Actions workflow in .github/workflows/validate.yml to use Node.js 22 (from 20).
• Align CI Node runtime with the required platform upgrade from Node 20 to Node 22.

[gemini-code-assist]

Note

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[google-cla]

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