not deployed: Fix Codeblock of arr.reduce() alternative

[akaguny]

#35 was fixed https://github.com/mfrachet/create-frontend-framework/blob/master/book/templating/template-literals.md but actual state of the book is broken https://mfrachet.github.io/create-frontend-framework/templating/template-literals.html#our-first-html-elements I have no ideas how fix. previous fixes was apply success (such as my fixes #26 )