Gemfile in in_threads-1.5.4 vs Gemfile in in_threads-1.6.0

@@ -3,9 +3,5 @@
 source 'https://rubygems.org'
 
 gemspec
 
 gem 'rspec-retry', '< 0.6.1' if RUBY_VERSION < '1.9'
-
-if RUBY_VERSION >= '2.0'
-  gem 'travis_check_rubies', '~> 0.2'
-end