.travis.yml in airbrussh-1.1.2 vs .travis.yml in airbrussh-1.2.0

@@ -20,6 +20,6 @@
   include:
     # Run Danger only once, on 2.4.0
     - rvm: 2.4.0
       script: bundle exec danger
 
-before_install: gem install bundler --conservative --version '~> 1.10'
+before_install: gem install bundler --conservative --version '~> 1.13.7'