Node 20 and dependency updates

[jreineckearm]

What it does

• Updates to node version 20.x.
• Updated some dependencies (vsce and node types).

Fixes CI after environment updates to default GitHub runners.

How to test

Review checklist

• as an author, I have thoroughly tested my changes and carefully followed the contribution guidelines

Reminder for reviewers

• as a reviewer, I agree to behave in accordance with the code of conduct

[colin-grant-work]

The changes look good to me. Running yarn audit, there are quite a few vulnerabilities, though mostly in our development dependencies. Is there interest in a broader dependency uplift to try to address some of those?

[jreineckearm]

Thanks for raising this, @colin-grant-work . Yes, I believe we need to do some housekeeping. I'll raise a separate issue as this may require a bit more testing.

I am keen to make a release by the end of the month to get updates from the last year out to the public. There is one docs PR and one release preps PR ongoing after which the time may be right. So, may only make that dependency update after the release to minimize risk of catching hidden last minute regressions.

[jreineckearm]

For completeness: raised #162 as a follow-up to sort outdated dependencies.