use latest version of ruby

junaruga · junaruga · commit 29b6a5560f01 · 2017-05-10T16:54:17.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,6 +1,6 @@
 language: ruby
 rvm:
-  - 2.3.3
-  - 2.4.0
+  - 2.3.4
+  - 2.4.1
   - ruby-head
 before_install: gem update bundler
