.travis.yml in test-kitchen-1.23.2 vs .travis.yml in test-kitchen-1.23.3

@@ -25,13 +25,9 @@
   only:
   - master
 
 matrix:
   include:
-    - rvm: 2.5.1
-      before_install:
-      # https://github.com/travis-ci/travis-ci/issues/8978
-      - gem update --system
     - rvm: 2.4.4
       # To run the proxy tests we need additional gems than what Test Kitchen normally uses
       # for testing
       gemfile: Gemfile.proxy_tests
       before_install: