[BUG] Spec tests fail in node 20.8.0+

[chrismclarke]

Describe the bug
Some scripts tests populate a virtual file system to test various file creation/modification methods, e.g. assets postprocessor spec.
These rely on the package mock-fs which is currently broken on Node 20
https://github.com/tschaub/mock-fs/issues/380
https://github.com/tschaub/mock-fs/issues/384

and may not be fixed any time soon...
https://github.com/tschaub/mock-fs/issues/383

To Reproduce
Using a system running Node 20.8.0:
yarn workspace scripts test

Additional context
Short term workaround is to avoid Node 20 (stick to 20.7.0 or 18) for CI and local tests.

I've tried replacing with alternatives but neither of the options below seem to be a perfect drop-in replacement:

mock-tmp
Uses slightly different folder structures which would mean refactoring tests

memfs
Can't find any way to force memfs methods to be called when running service code. Likely custom utility functions required to replace library fs methods with memfs and restore after tests, in the same way that mock-fs does

The other workaround is to use all async methods for fs operations both in spec and test code (importing from fs/promises), however

Spike PR used while testing possible fixes: #2186

[chrismclarke]

Just to note, recent angular 17.3 update requires "^18.13.0 || >=20.9.0"
which means either using v18 (>18.13.0), or v20 (>20.9.0)

So if wanting to update to angular 17.3 or beyond (when released), will either need developers using node 20.7.0 (last known compatible) to downgrade to node 18 - which isn't ideal.

As of recent comment mock-fs repo owner says open to PRs but not planning to fix, so we may need to discuss alternatives when next planning for core updates
https://github.com/tschaub/mock-fs/issues/384

May be of interest @jfmcquade