bump to Ruby 2.3.2

hsbt · hsbt · commit 732c2b7ace40 · 2016-11-21T12:04:42.000+09:00
diff --git a/Gemfile b/Gemfile
@@ -1,5 +1,5 @@
 source "https://rubygems.org"
-ruby ENV['CUSTOM_RUBY_VERSION'] || '2.3.1'
+ruby ENV['CUSTOM_RUBY_VERSION'] || '~> 2.3.2'
 
 gem 'rake'
 gem 'jekyll', '~> 3.0'
