Update action to node20

[takost]

Description:
Node 16 has reached end-of-life on 11 Sep 202.
This PR updates the default runtime to node20, rather then node16.

This is supported on all Actions Runners v2.308.0 or later.

Related issue:
Add link to the related issue.

Check list:

• Mark if documentation changes are required.
• Mark if tests were added or updated to cover the changes.

[dlemstra]

You might also want to update node_modules/@types/node and maybe also some of the other packages? That can fix this critical in one of the dependencies:

@babel/traverse <7.23.2
Severity: critical
Babel vulnerable to arbitrary code execution when compiling specifically crafted malicious code - GHSA-67hx-6x53-jw92
fix available via npm audit fix
node_modules/@babel/traverse

[takost]

@dlemstra Thanks for your comment, I'll try to update packages.
But could you please help me with the failing test? Looks like test from the externals is out-dated, and I'm not familiar with the process of update of this script.

[dlemstra]

It looks like someone else created a PR that addresses this issue here: #484?

[takost]

@dlemstra I will close my PR in favour of #484