fix(build): copy images that are only in default locale to l10n folder

[yin1999]

Summary

Fixes: #5652

Problem

The images used in live sample ({{EmbedLiveSample}}) are not served (404) when they are not duplicated on mdn/translated-content.

⚠️ Blocked by: #7921

Solution

See: #5652 (comment)

Copy images to l10n built folders.

We have serve the image files correctly in yarn-server, so we should only copy the images when in static build mode.

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Screenshots

See testing.

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How did you test this change?

run yarn test:testing.

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[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[yin1999]

@caugner, may I get a review :)

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[github-actions]

This pull request has merge conflicts that must be resolved before it can be merged.

[caugner]

@LeoMcA I would suggest that we handle this instead in our Cloud Function here:

https://github.com/mdn/yari/blob/f18d609c6ddfda87efca707234f9d4a6c49798df/cloud-function/src/handlers/proxy-content.ts#L29C1-L35

If we don't find an asset in /fr/..., try it again with /en-us/.

[yin1999]

We may also need to consider mdn/translated-content#7648

[caugner]

LGTM and tested locally by comparing full builds of this branch vs main, just two nits (one about naming the map variable, and another about reusing findByURLWithFallback). 🚀

[yin1999]

Thanks for the suggestions @caugner. I've pushed 1da8c43 to resolve them :)

[caugner]

LGTM, thanks a lot! 🚀

[caugner]

Thank you @yin1999. I triggered an xyz-build, and once that has finished, you should be able to see the results here.

If all goes well, the images that are missing here on prod, should appear here on xyz.

[yin1999]

Thank you @yin1999. I triggered an xyz-build, and once that has finished, you should be able to see the results here.

If all goes well, the images that are missing here on prod, should appear here on xyz.

I'll keep an eye on the build results. Thanks for your advice as well :)

[yin1999]

Hi @caugner. I could actually see the image in 'zh-CN'. But the live sample in xyz build seems to be broken. I just use my phone to view this page, so I couldn't give more information (It's late at night in China, and I'm going to 🛏️). I think it's your time to fix this ;)

[caugner]

(The live samples are broken on xyz probably because we didn't update the workflow when the playground landed.)