added rubocop

Gemfile

@@ -1,32 +1,31 @@
 # frozen_string_literal: true
 
-source "https://rubygems.org"
+source 'https://rubygems.org'
 
+gem 'roda', '~> 3.72'
 
-gem "roda", "~> 3.72"
+gem 'sequel', '~> 5.72'
 
-gem "sequel", "~> 5.72"
+gem 'tilt', '~> 2.2'
 
-gem "tilt", "~> 2.2"
+gem 'sqlite3', '~> 1.6'
 
-gem "sqlite3", "~> 1.6"
-
-gem "erubi", "~> 1.12"
+gem 'erubi', '~> 1.12'
 
 group :test do
+  gem 'cucumber', '~> 9.0'
 
-  gem "cucumber", "~> 9.0"
+  gem 'capybara', '~> 3.39'
 
-  gem "capybara", "~> 3.39"
+  gem 'rspec', '~> 3.12'
 
-  gem "rspec", "~> 3.12"
+  gem 'selenium-webdriver', '~> 4.13'
 
-  gem "selenium-webdriver", "~> 4.13"
-
-  gem "simplecov"
+  gem 'simplecov'
 
+  gem 'rubocop', require: false
 end
 
-gem "puma", "~> 6.4"
+gem 'puma', '~> 6.4'
 
-gem "rackup", "~> 2.1"
+gem 'rackup', '~> 2.1'