.travis.yml in recog-2.3.7 vs .travis.yml in recog-2.3.8

@@ -1,12 +1,10 @@
 language: ruby
 sudo: false
 cache: bundler
 rvm:
-  - '2.3.8'
-  - '2.4.5'
-  - '2.5.3'
-  - '2.6.1'
+  - '2.5.8'
+  - '2.6.6'
   - 'jruby-9.1.9.0'
 jdk:
   - openjdk8
 matrix:
   allow_failures: