Auto correct: Style/StringLiterals in top level dir

Gemfile

 # frozen_string_literal: true
-source 'https://rubygems.org'
-gemspec unless ENV['USE_INSTALLED_GUARD'] == '1'
-gem 'rake'
+source "https://rubygems.org"
+gemspec unless ENV["USE_INSTALLED_GUARD"] == "1"
+gem "rake"
 # The development group will not be
 # installed on Travis CI.
@@ -17,18 +17,18 @@ group :development do
   # on HoundCI's side.
   #
   # See https://github.com/houndci/hound/issues/1250
-  gem 'rubocop', '0.54.0', require: false
-  gem 'guard-rubocop', require: false
-  gem 'guard-ronn', require: false, platform: :mri
-  gem 'redcarpet', require: false, platform: :mri
-  gem 'yard', require: false, platform: :mri
+  gem "rubocop", "0.54.0", require: false
+  gem "guard-rubocop", require: false
+  gem "guard-ronn", require: false, platform: :mri
+  gem "redcarpet", require: false, platform: :mri
+  gem "yard", require: false, platform: :mri
   # Used for release
-  gem 'gems', require: false, platform: :mri
-  gem 'netrc', require: false, platform: :mri
-  gem 'octokit', require: false, platform: :mri
+  gem "gems", require: false, platform: :mri
+  gem "netrc", require: false, platform: :mri
+  gem "octokit", require: false, platform: :mri
 end
 # The test group will be
@@ -36,22 +36,22 @@ end
 #
 group :test do
   # Both guard-rspec and guard-cucumber are used by cucumber features
-  gem 'guard-cucumber', '~> 2.1', require: false
-  gem 'guard-rspec', require: false
-  gem 'aruba', '~> 0.9', require: false
-  gem 'codeclimate-test-reporter', require: nil
-  gem 'notiffany', '>= 0.0.6', require: false
-  gem 'rspec', '>= 3.0.0', require: false
+  gem "guard-cucumber", "~> 2.1", require: false
+  gem "guard-rspec", require: false
+  gem "aruba", "~> 0.9", require: false
+  gem "codeclimate-test-reporter", require: nil
+  gem "notiffany", ">= 0.0.6", require: false
+  gem "rspec", ">= 3.0.0", require: false
 end
 # Needed for Travis
 # See http://docs.travis-ci.com/user/languages/ruby/#Rubinius
 #
 platforms :rbx do
-  gem 'json'
-  gem 'psych'
-  gem 'racc'
-  gem 'rubinius-coverage'
-  gem 'rubysl', '~> 2.0'
+  gem "json"
+  gem "psych"
+  gem "racc"
+  gem "rubinius-coverage"
+  gem "rubysl", "~> 2.0"
 end