CI: Use 2.5.5, 2.6.2

Author: olleolleolle

.travis.yml

@@ -7,8 +7,8 @@ matrix:
   fast_finish: true
   include:
     # Latest versions first
-    - name: MRI 2.6.1 Latest
-      rvm: 2.6.1
+    - name: MRI 2.6.2 Latest
+      rvm: 2.6.2
     - name: JRuby 9.2.6.0 Latest on Java 11
       rvm: jruby-9.2.6.0
       jdk: oraclejdk11
@@ -18,14 +18,14 @@ matrix:
     - name: TruffleRuby Latest
       rvm: truffleruby
     - name: YARD uptodate in docs
-      rvm: 2.6.1
+      rvm: 2.6.2
       script:
       - bundle install --with documentation
       - bundle exec rake yard:master:uptodate
 
     # Older versions follow
-    - name: MRI 2.5.3
-      rvm: 2.5.3
+    - name: MRI 2.5.5
+      rvm: 2.5.5
     - name: MRI 2.4.5
       rvm: 2.4.5
     - name: MRI 2.3.8