chore: update version of Node.js used for testing

[mhdawson]

Summary

Update tests to use Node.js 18 instead of 16 since support for 16 has been removed

Use Cases

Checklist

• [X] I have viewed, signed, and submitted the Contributor License Agreement.
• [X] I have linked issue(s) that this PR should close using keywords or the Github UI (See docs)
• [X] I have added an integration test, if necessary.
• [X] I have reviewed the styleguide for guidance on my code quality.
• [x] I'm happy with the commit history on this PR (I have rebased/squashed as needed).