Document our preference for array literals until we enable a Cop
What does this MR do?
It documents our preference for always using []
delimiters instead of ()
for array literals.
Ideally we want to enable a Cop for that.
Why was this MR needed?
Because when suggesting this change in merge request reviews, developers often points to our Ruby style guide which tells another rule: https://github.com/bbatsov/ruby-style-guide#percent-literal-braces