Fix tests on node 20

[everett1992]

This includes @andrewnicols's changes from #381

All unit tests pass on node 20 (and 22)
I have not written any new tests, or checked that any new APIs work correctly.
This at-least partially fixes #384. I tested these changes in an application that was failing with mock-fs 5.2.0 and node 20

[tschaub]

Thanks, @everett1992!

Could you add 20 to the list of node versions here:

mock-fs/.github/workflows/test.yml

Lines 26 to 28 in b0808c5

	node:
	- 16
	- 18

And then the readme can be updated here:

mock-fs/readme.md

Line 273 in ea6e334

Tested on Linux, OSX, and Windows using Node 16 through 18. Check the tickets for a list of [known issues](https://github.com/tschaub/mock-fs/issues).

It looks like tests also pass on Node 22. If you find the same, we could add 22 to the list as well.

[tschaub]

Oh, I forgot about all the ignored tests. So not right to imply that all "tests pass" on Node 20 and 22.

Do you know if there are tests that are currently ignored that would pass with your changes?

[everett1992]

Doesn't look like I fixed any of those

1) The API
       mock.fs()
         generates a mock fs module with a mock file system:
     TypeError: mock.fs is not a function
      at Context.<anonymous> (test/lib/index.spec.js:350:27)
      at process.processImmediate (node:internal/timers:491:21)

  2) The API
       mock.fs()
         passes options to the FileSystem constructor:
     TypeError: mock.fs is not a function
      at Context.<anonymous> (test/lib/index.spec.js:361:27)
      at process.processImmediate (node:internal/timers:491:21)

  3) The API
       mock.fs()
         accepts an arbitrary nesting of files and directories:
     TypeError: mock.fs is not a function
      at Context.<anonymous> (test/lib/index.spec.js:376:27)
      at process.processImmediate (node:internal/timers:491:21)

[everett1992]

I think those disabled mock.fs tests should be removed, since mock.fs was removed in v4

Upgrading to version 4
The mock.fs() function has been removed. This returned an object with fs-like methods without overriding the built-in fs module.

https://github.com/tschaub/mock-fs/blob/main/changelog.md#400

[tschaub]

I think those disabled mock.fs tests should be removed, since mock.fs was removed in v4

Thanks for the reminder! Those tests could have been removed instead of ignored in https://github.com/tschaub/mock-fs/pull/182/files#diff-e78e0b8d4a6016fffbd3160920548d5860afed84b611d22f4f6e0c42609d7ce6.

[tschaub]

Thank you @everett1992 and @andrewnicols!