Use latest stable releases of all rubies in CI

Author: ivoanjo

.travis.yml

@@ -4,17 +4,16 @@ sudo: false
 
 matrix:
   include:
-    - rvm: 2.3.1
+    - rvm: 2.4.1
+    - rvm: 2.4.1
       script:
         - bundle exec danger
-    - rvm: 2.3.1
-    - rvm: 2.3.0
-    - rvm: 2.2.5
-    - rvm: 2.4.0
+    - rvm: jruby-9.1.12.0
+    - rvm: jruby-head
+    - rvm: 2.2.7
+    - rvm: 2.3.4
     - rvm: rbx-2
     - rvm: ruby-head
-    - rvm: jruby-head
-    - rvm: jruby-9.1.7.0
   allow_failures:
     - rvm: ruby-head
     - rvm: jruby-head