📝 Update `Annotated` notes in `docs/en/docs/tutorial/schema-extra-example.md` (#9620)

📝 Update `Annotated` notes in `docs/en/docs/tutorial/schema-extra-example.md` (#9620)

Update for docs/tutorial/schema-extra-example.md

When working on the translation, I noticed that this page is missing the annotated tips that can be found in the rest of the documentation (I checked, and it's the only page where they're missing).