Updated node version from 18 to 20

[rimashah25]

Upgrading node version to 20.11.0

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Which Traffic Control components are affected by this PR?

• CDN in a Box
• Automation (GitHub Actions)

What is the best way to verify this PR?

Pass all GH actions

If this is a bugfix, which Traffic Control versions contained the bug?

N/A

PR submission checklist

• [ ] This PR has tests
• [ ] This PR has documentation
• [ ] This PR has a CHANGELOG.md entry
• [x] This PR DOES NOT FIX A SERIOUS SECURITY VULNERABILITY (see the Apache Software Foundation's security guidelines for details)