Docs: add warning callout for Yarn Berry

[julien-deramond]

Description

Based on the discussion in #40933 and the solution brought to build our Sass & JS example in #40933 (comment), this PR suggests a small enhancement to at leasts mention this "trick".

The approach is that we consider that most folks are still on Yarn (Classic), but we mention a way to make our examples work with Yarn Berry too to unblock some others.

Another approach would be to create a dedicated example in twbs/examples and link to it. But, TBH, I don't have time for it, and I'm not sure whether it's needed for now.

Type of changes

• Docs enhancement

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
• I have updated the documentation accordingly
• (N/A) I have added tests to cover my changes
• All new and existing tests passed

Live previews

• https://deploy-preview-41036--twbs-bootstrap.netlify.app/docs/5.3/getting-started/download/#yarn

[louismaximepiton]

The rendering looks a bit weird. Maybe we should remove the .bd-callout .highlight rule.
On the content, I tried and it works pretty well, I'm just wondering where it should be placed tbh. Maybe inside the ## Examples paragraph ? It looks weird in here since we only mention the library.

[julien-deramond]

On the content, I tried and it works pretty well, I'm just wondering where it should be placed tbh. Maybe inside the ## Examples paragraph ? It looks weird in here since we only mention the library.

I chose this place because this is the only place where "Yarn" is mentioned. So I'd suppose that Yarn users would end up here at some point.

The rendering looks a bit weird

You mean the code part within the warning callout? FYI, we got the same rendering at https://deploy-preview-41036--twbs-bootstrap.netlify.app/docs/5.3/components/tooltips/#usage