feat: add lessons learned for epicweb-dev#1

src/exercise/01.md

@@ -1,8 +1,14 @@
- # Simple Data-fetching
+# Simple Data-fetching
 
 ## 📝 Your Notes
 
-Elaborate on your learnings here in `src/exercise/01.md`
+In this exercise we learned how to use `React.Suspense` to fetch data, as soon
+as we have enough information to fetch data. We render our components and,
+while the result is not available we show a `<PokemonInfoFallback />`. Finally,
+when the request terminates, `React.Suspense` triggers a re-render which allows
+us to show more meaningful items. In the next lessons we are going to use this
+functinality to "Fetch data as we render", by loading the data and the
+components asynchronously.
 
 ## Background