Update refs-and-the-dom.md (#8250)
Update refs-and-the-dom.md (#8250)

Since a lot of projects use [airbnb eslint config](https://www.npmjs.com/package/eslint-config-airbnb) where [this rule](http://eslint.org/docs/rules/no-return-assign) is enabled (and its a good rule) some people might get confused when they are trying this out in their project.
(cherry picked from commit f4059e5e5b426224721b19f03fecea94335a5d3b)

with-git/react,with-git/react,with-git/react,with-git/react,with-git/react,with-git/react,with-git/react