Modify pre-build hook to include npm install

[clemcode]

📝 What does this PR do?

Modify pre-build hook to include npm install after following the docs and getting a command not found error on build

🧪 Type of Change

• ⚠️ Bug fix
• 📅 Changelog update
• 📚 Documentation update
• ✨ New content/feature
• 🔧 Technical/maintenance

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• I have read the contributing guidelines
• The content is accurate and links work
• The site builds without errors

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@CleverCloud/reviewers

[github-actions]

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[davlgd]

There is no need to add npm install, as it's automatically done during the build phase on a Node.js & Bun application. I suppose the problem here is more that the npm run build command is launched during the pre-build hook (so before the npm install).

Can you try to replace this command with clever env set CC_POST_BUILD_HOOK "npm run build" and tell me if it works ? (or I'll try later to check).