.travis.yml in test-kitchen-1.14.2 vs .travis.yml in test-kitchen-1.15.0

- old
+ new

@@ -1,8 +1,7 @@
 language: ruby
 
 rvm:
-  - 2.1.9
   - 2.2.5
   - 2.3.1
   - ruby-head
 
 env: