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.
* DEV: Sanitize HTML admin inputs
This PR adds on-save HTML sanitization for:
Client site settings
translation overrides
badges descriptions
user fields descriptions
I used Rails's SafeListSanitizer, which [accepts the following HTML tags and attributes](018cf54073/lib/rails/html/sanitizer.rb (L108))
* Make sure that the sanitization logic doesn't corrupt settings with special characters
This change both speeds up specs (less strings to allocate) and helps catch
cases where methods in Discourse are mutating inputs.
Overall we will be migrating everything to use #frozen_string_literal: true
it will take a while, but this is the first and safest move in this direction
