.travis.yml in openapi_parser-0.12.1 vs .travis.yml in openapi_parser-0.13.0

@@ -5,12 +5,13 @@
 language: ruby
 
 rvm:
   - 2.3.8
   - 2.4.10
-  - 2.5.8
-  - 2.6.6
-  - 2.7.1
+  - 2.5.9
+  - 2.6.7
+  - 2.7.3
+  - 3.0.1
   - ruby-head
 
 cache: bundler
 
 before_script: