Add simple example and import statement to logger API docs

[Zenahr]

Have you read the Contributing Guidelines on issues?

• I have read the Contributing Guidelines on issues.

Description

Affecting: https://docusaurus.io/docs/api/misc/@docusaurus/logger

At the very least, having sample code on how to import the logger and at one logger call would be great (simple usage, besides the template literal method, e.g. logger.green("some text")). That way, readers wouldn't have to browse the Docusaurus source code just to know how to use the logger package.

The logger is useful not just for plugin authors, but also if you've got any complex React components you'd like some logging on for errors etc.

Self-service

• I'd be willing to address this documentation request myself.

[ArslanYM]

Can i work on this?

[Josh-Cena]

@ArslanYM Thanks, but I will work on this myself. It's already assigned.

[ArslanYM]

ok john cena

[Zenahr]

@ArslanYM if you're eager to contribute, feel free to take on my MR #8704 (I was going to work on this in a couple days, but if you'd like you can continue it.)

[ArslanYM]

I would love to work on this #8704 but its kind of unclear to me what exactly im supposed to do