Remove redundant quotation

I'm not sure this quotation adds much beyond what is already said in the "Extract general-purpose ViewComponents" and I found the association with this particular individual a bit jarring as I was reading this section of the docs today, particularly in light of this projects clear and welcoming code of conduct.

Author: chrislo

docs/best_practices.md

@@ -42,8 +42,6 @@ For example, `User::AvatarComponent` accepts a `User` ActiveRecord object and re
 
 ### Extract general-purpose ViewComponents
 
-"Good frameworks are extracted, not invented" - [DHH](https://dhh.dk/arc/000416.html)
-
 Just as ViewComponent itself was extracted from GitHub.com, general-purpose components are best extracted once they've proven helpful across more than one area:
 
 1. Single use-case component implemented.