test: remove fs mocked test

[43081j]

Removes the skipped test since we can't really do it in ES modules anyway (as we can't mock ESM exports).

[43081j]

@paulmillr there are a couple of other tests skipped. do you know why?

this one:

chokidar/src/index.test.mts

Line 674 in 7b3e627

describe.skip('Skipping gh-682: should detect unlink', () => {

and this one:

chokidar/src/index.test.mts

Line 1770 in 7b3e627

it.skip('should watch paths that were unwatched and added again', async () => {

do you know if/how we can re-enable them?

[paulmillr]

they've been failing forever I think. Hard to remember.