docs(zh-cn): [event-handling.md] split comment into two lines to maintain syntax highlighting

[DDDDD12138]

Thank you @lxKylin for the Chinese proofreading of the event-handling.md file in #2572, but one example's syntax highlighting did not match:

Before:

After:

Description

I think it's better not to change the original line numbers, as it will facilitate future updates.
我想还是不要改动到原有的行数，也方便后续更新

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[Jinjiang]

首先感谢贡献，目前保持行号完全一致是不可能的，比如有的地方一大段英文中间会有折行，这对于中文来说会额外产生一个空格。所以我们不得不把这样的折行全部去掉。所以该 PR 的改动在我看来是没有必要的。望理解。再次感谢你的 PR。