.travis.yml in postrank-uri-1.0.23 vs .travis.yml in postrank-uri-1.0.24

@@ -1,11 +1,11 @@
 language: ruby
 cache: bundler
 rvm:
-  - 2.1
-  - 2.2
-  - 2.3
-  - 2.4.0
+  - 2.3.8
+  - 2.4.5
+  - 2.5.3
+  - 2.6.1
 before_install:
   - gem install bundler
 install:
   - bundle install --jobs=3 --retry=3
   - bundle exec appraisal install