.travis.yml in ruby_px-0.5.0 vs .travis.yml in ruby_px-0.6.0

@@ -1,4 +1,5 @@
 language: ruby
 rvm:
-  - 2.2.3
-before_install: gem install bundler -v 1.10.6
+  - 2.7.1
+  - 2.6.3
+before_install: gem install bundler