Change to update to latest rubies

piotrmurach · piotrmurach · commit cf128cecd727 · 2017-11-19T17:32:21.000Z
diff --git a/.travis.yml b/.travis.yml
@@ -2,13 +2,14 @@
 language: ruby
 sudo: false
 cache: bundler
+before_install: "gem update bundler"
 script: "bundle exec rake ci"
 rvm:
   - 2.0.0
   - 2.1.10
-  - 2.2.6
-  - 2.3.3
-  - 2.4.1
+  - 2.2.8
+  - 2.3.5
+  - 2.4.2
   - ruby-head
   - jruby-9000
   - jruby-head
