Handle delay of nested `setTimeout` calls

After several nested `setTimeout` calls, the minimum delay should be 4ms

https://developer.mozilla.org/en-US/docs/Web/API/Window/setTimeout#reasons_for_delays_longer_than_specified

Start by locating the setTimeout implementation and review the linked MDN guidance on nested calls and minimum delays. Reproduce several nested setTimeout calls, then verify that the minimum delay becomes 4ms after the specified nesting depth and add or update coverage for that behavior.

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