Original solution to use `description` instead of `text_description` was wrong: https://github.com/discourse/discourse/pull/20436
Problem is that we have to escape HTML tags.
However, we would like to use escape method which is keep `/` intact. Expected behavior is given by ERB::Util.html_escape instead of Rack::Utils.escape_html
/t/92015
It's very easy to forget to add `require 'rails_helper'` at the top of every core/plugin spec file, and omissions can cause some very confusing/sporadic errors.
By setting this flag in `.rspec`, we can remove the need for `require 'rails_helper'` entirely.
