How to output `"🐍"`

[youtux]

Hi, I'm trying to address this issue in yamlfix, and it seems that it comes down to how ruyaml applies escaping.

I'm having troubles figuring out how to have ruyaml output the following document (the snake unicode character enclosed by double quotes):

--- "🐍"

Using the yamlfix configuration posted in lyz-code/yamlfix#227, I ruyaml would output:

--- "\U0001F40D"

Do you have any suggestions?