Rely on rubocop-github for Ruby formatting

script/validate-html

@@ -1,13 +1,13 @@
 #!/usr/bin/env ruby
 # frozen_string_literal: true
 
-require 'w3c_validators'
+require "w3c_validators"
 
 def validator(file)
   extension = File.extname(file)
-  if extension == '.html'
+  if extension == ".html"
     W3CValidators::NuValidator.new
-  elsif extension == '.css'
+  elsif extension == ".css"
     W3CValidators::CSSValidator.new
   end
 end
@@ -18,11 +18,11 @@ def validate(file)
   path = File.expand_path "../_site/#{file}", __dir__
   results = validator(file).validate_file(path)
 
-  return puts 'Valid!' if results.errors.empty?
+  return puts "Valid!" if results.errors.empty?
 
   results.errors.each { |err| puts err.to_s }
   exit 1
 end
 
-validate 'index.html'
-validate File.join 'assets', 'css', 'style.css'
+validate "index.html"
+validate File.join "assets", "css", "style.css"