test: Add Node 20 to CI matrix

[BilalQamar95]

Description

As a first step in the upgrade to Node 20, add it to the CI matrix as a non-blocking test.

See the tracking issue for further information.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.27%. Comparing base (e7160b2) to head (b28deb5).
Report is 13 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3234   +/-   ##
=======================================
  Coverage   93.27%   93.27%           
=======================================
  Files         249      249           
  Lines        4401     4401           
  Branches     1002     1039   +37     
=======================================
  Hits         4105     4105           
+ Misses        293      290    -3     
- Partials        3        6    +3     

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[openedx-semantic-release-bot]

🎉 This PR is included in version 22.9.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀