.travis.yml in email_inquire-0.8.0 vs .travis.yml in email_inquire-0.9.0

@@ -5,11 +5,12 @@
   - cp -f .rspec.travis .rspec
 bundler_args: --without local
 dist: trusty
 language: ruby
 rvm:
-  - 2.3.6
-  - 2.4.3
-  - 2.5.0
+  - 2.3.8
+  - 2.4.5
+  - 2.5.3
+  - 2.6.0
 script:
   - bundle exec rake ci
 sudo: false