language: ruby
rvm:
  - 2.1
  - 2.2
  - 2.3.0
  - 2.3.1
  - 2.3.2
  - 2.3.3

branches:
  only:
    - master

language: ruby
rvm:
  - 2.1
  - 2.2
  - 2.3
  - 2.4
  - 2.5

branches:
  only:
    - master

Test against Ruby 2.4 and 2.5
[CI] Test against Ruby 2.4 and 2.5