Remove useless patch for Ruby

See: rubyconfig/config#255

Author: n-rodriguez

lib/active_settings/config.rb

@@ -122,13 +122,7 @@ def __convert(hash)
             value
           end
 
-        if s.respond_to?(:[]=)
-          s[key] = new_val
-        else
-          s.new_ostruct_member(key)
-          s.send("#{key}=".to_sym, new_val)
-        end
-
+        s[key] = new_val
       end
       s
     end