fix(storybook): generate SB website in _site intead of site

[julien-deramond]

Related issues

Linked to the following issue mentioned in #1626:

Error message when running npm run storybook-build and then npm run storybook

...
> boosted@5.2.1 docs-vnu
> node build/vnu-jar.js

"file:/Users/ju/Orange-Boosted-Bootstrap/_site/storybook/index.html":1.38-1.60: info warning: Self-closing tag syntax in text/html documents is widely discouraged; it's unnecessary and interacts badly with other HTML features (e.g., unquoted attribute values). If you're using a tool that injects self-closing tag syntax into all void elements, without any option to prevent it from doing so, then consider switching to a different tool.
"file:/Users/ju/Orange-Boosted-Bootstrap/_site/storybook/index.html":1.87-^C

Description

This error is generated by the HTML validator that scans our site directory. Since Storybook website is generated in site, the HTML validator is not very happy with the self-closing tags.

But in fact, there's no reason to generate Storybook website in site. After the release, we're going to copy _site and not site into gh-pages.

When running locally npm run storybook, Storybook website is not generated as HTML files.

So the only thing to change here is to keep it working with Netlify which needs to have site/storybook directory. I have created a special npm command to differenciate the normal build and the one reserved to Netlify.

Non-regression testing

• npm run storybook works locally and doesn't generate _site/storybook nor site/storybook
• running npm run storybook-build and then npm run storybook works without the error mentioned in the description
• npm run storybook-build creates _site/storybook but nothing in site
• npm run release creates _site/storybook but nothing in site

Types of change

• Bug fix (non-breaking which fixes an issues)

Live previews

• https://deploy-preview-1660--boosted.netlify.app/storybook

Checklist

• I have read the contributing guidelines
• My code follows the code style of the project (using npm run lint)
• My change introduces changes to the documentation
• All new and existing tests passed

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[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
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No Coverage information
0.0% Duplication

[louismaximepiton]

Sounds great ! Couldn't spot any breaking change and will clear some stuff.