[flake8-async] Make ASYNC110 example error out-of-the-box

[MeGaGiGaGon]

Summary

Part of #18972

This PR makes async-busy-wait (ASYNC110)'s example error out-of-the-box

Old example

DONE = False


async def func():
    while not DONE:
        await asyncio.sleep(1)

New example

import asyncio

DONE = False

async def func():
    while not DONE:
        await asyncio.sleep(1)

Test Plan

N/A, no functionality/tests affected

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

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