setup.rb in sinatra-contrib-3.0.0

- old
+ new

@@ -1,12 +1,14 @@
+# frozen_string_literal: true
+
 require 'sinatra/base'
 require 'sinatra/contrib/version'
 
 module Sinatra
   module Contrib
     module Loader
       def extensions
-        @extensions ||= {:helpers => [], :register => []}
+        @extensions ||= { helpers: [], register: [] }
       end
 
       def register(name, path)
         autoload name, path, :register
       end