feat: add warning about the real world

Author: honzajavorek

sources/academy/webscraping/scraping_basics_python/_exercises.mdx

@@ -1,3 +1,9 @@
 ## Exercises
 
 These challenges are here to help you test what you’ve learned in this lesson. Try to resist the urge to peek at the solutions right away. Remember, the best learning happens when you dive in and do it yourself!
+
+:::caution Real world
+
+You're about to touch the real web, which is practical and exciting! But websites change, so some exercises might break. If you run into any issues, please leave a comment below or [file a GitHub Issue](https://github.com/apify/apify-docs/issues).
+
+:::