EDU-13989: Review Preact doc

[Mariana-Caetano]

Types of changes

• New content (guides, endpoints, app documentation)
• Improvement (make a documentation even better)
• Fix (fix a documentation error)
• Spelling and grammar accuracy (self-explanatory)

[github-actions]

Preview Links

Open this URL to set up the portal with this branch changes.

You can now access the edited pages with the following URLs:

• Couldn't find the corresponding page for docs/faststore/docs/managing-performance/improving-store-performance-with-preact.mdx. Have you added improving-store-performance-with-preact to the navigation.json file? Maybe you can find it in https://developers.vtex.com/docs/guides/faststore/managing-performance-improving-store-performance-with-preact

[github-actions]

Navigation Preview Link

No changes detected in the navigation.json file