@async/pool_test.ts is flaky

[BlackAsLight]

The first test for @async/pool appears to be flaky due to it expecting the execution to happen within a time range but if the execution is slow then it fails.

The Test:

std/async/pool_test.ts

Line 11 in e3dc30a

Deno.test("pooledMap()", async () => {

Its failure: https://github.com/denoland/std/actions/runs/12616622006/job/35158046648#step:4:1

[lionel-rowe]

Dupe of #6287