Gemfile in string_tools-0.15.0 vs Gemfile in string_tools-0.16.0

@@ -1,4 +1,7 @@
+# frozen_string_literal: true
 source 'https://rubygems.org'
 
 # Specify your gem's dependencies in string_tools.gemspec
 gemspec
+
+gem 'actionpack', '~> 4.0.13', require: false