Update requirements.txt

[wznmickey]

aiocqhttp update the package and requirement in 0.7.0 and the functions related to timed tasks will not work.
Reference : https://aiocqhttp.nonebot.dev/#/changelog#v070

[BoYanZh]

Can the timed task be fixed with the latest version of aiocqhttp?

[wznmickey]

Can the timed task be fixed with the latest version of aiocqhttp?

Yes, adding asyncio.get_event_loop().run_forever() at the end of the sche function will make work well.
However, whether it will cause side effects on other functions is not sure because I still not find what is new in the higher version make the previous code not run well.