Gemfile in tjson-0.3.0 vs Gemfile in tjson-0.4.0

@@ -1,16 +1,17 @@
 # frozen_string_literal: true
 
 source "https://rubygems.org"
+ruby RUBY_VERSION
 
 gemspec
 
 group :development do
   gem "guard-rspec"
 end
 
 group :development, :test do
   gem "rake"
-  gem "toml-rb"
   gem "rspec", "~> 3.5"
-  gem "rubocop", "0.44.1"
+  gem "rubocop", "0.48.1"
+  gem "toml-rb"
 end