When serializing, preserve Unicode information

[ponponon]

Hi, I'm here again, I resubmitted the pull request.

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👇 Here is the original content：

I want to keep the original information of the Unicode code and not serialize it to ASCII

In [2]: json.dumps({"中文":"你好"})
Out[2]: '{"\\u4e2d\\u6587": "\\u4f60\\u597d"}'

In [3]: json.dumps({"中文":"你好"},ensure_ascii=False)
Out[3]: '{"中文": "你好"}'

[Delgan]

All good, thanks for your time and sorry again for my mistake in #574. 🙏

I discussed using ensure_ascii=False in #339 (comment) but I hadn't taken the time to add it.

[ponponon]

It's a pleasure, this is my first pull request for an open source project, feel loguru this great work, you are great open source author

[Delgan]

This is so kind of you, thanks! I hope this makes you willing to keep contributing to open source. 🚀