Fix broken exercises

[honzajavorek]

When working on #2097, I found out the following exercises don't work anymore, because the target sites now aggressively protect against scraping and thus are not suitable for a simple exercise:

• AliExpress - fixed, I changed it to LEGO in chore: test Academy exercises #2097 itself
• npm registry
• Netflix ratings
• Wikipedia
• stock numbers in https://warehouse-theme-metal.myshopify.com/collections/sales
• F1 Academy
• ...