Update rubopcop (#227)

* Update rubopcop [WIP]

* Further rubocop fixes

* Fix rubocop-rails cops

* Fix spec

* Disable rubocop suggestions

* Run rubocop in github actions rather than in codeclimate

Gemfile

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org'
 gemspec
 
@@ -14,7 +16,8 @@ group :development do
   gem 'rspec-its', '~> 1.3.0'
   gem 'rspec-rails', '~> 4.0.2'
 
-  gem 'rubocop', '~> 0.52.1'
+  gem 'rubocop', '~> 1.59.0'
+  gem 'rubocop-rails', '~> 2.23.1'
 
   gem 'coveralls', '~> 0.8.23', require: false
 end