.travis.yml in exp_retry-0.0.12 vs .travis.yml in exp_retry-0.0.13

@@ -6,9 +6,11 @@
     - "/^v[0-9]+\\.[0-9]+\\.[0-9]+(?:-.*)?/"
 notifications:
   email:
     on_success: change
     on_failure: always
+before_install:
+  - gem install bundler -v '< 2'
 before_script:
   - curl -L https://codeclimate.com/downloads/test-reporter/test-reporter-latest-linux-amd64 > ./cc-test-reporter
   - chmod +x ./cc-test-reporter
   - ./cc-test-reporter before-build
 script: