.travis.yml in fluent-plugin-string-scrub-1.0.0 vs .travis.yml in fluent-plugin-string-scrub-1.0.1

@@ -4,10 +4,13 @@
 rvm:
   - 2.1
   - 2.2
   - 2.3
   - 2.4
-  - 2.5.2
+  - 2.5
+  - 2.6
+  - 2.7
+  - 3.0
 
   #- ruby-head
 gemfile:
   - Gemfile
 before_install: