.gitlab-ci.yml in atd-0.4.0 vs .gitlab-ci.yml in atd-0.5.0

@@ -1,13 +1,64 @@
-image: ruby:2.3.1
+image: ruby:2.4.0
 
 before_script:
   - ruby -v
   - which ruby
+  - gem environment
+  - gem install rubygems-update
+  - gem install rubygems-update --version 2.6.3
+  - gem update --system 2.6.10
   - gem install bundler --no-ri --no-rdoc
+  - gem environment
   - bundle install --jobs $(nproc)  "${FLAGS[@]}"
 
-test:
+test-2.4.0:
+  image: ruby:2.4.0
+  script:
+    - bundle exec rake test
+
+test-2.3.3:
+  image: ruby:2.3.3
+  script:
+    - bundle exec rake test
+
+test-2.3.2:
+  image: ruby:2.3.2
+  script:
+    - bundle exec rake test
+
+test-2.3.1:
+  image: ruby:2.3.1
+  script:
+    - bundle exec rake test
+
+test-2.3.0:
+  image: ruby:2.3.0
+  script:
+    - bundle exec rake test
+
+test-2.2.6:
+  image: ruby:2.2.6
+  script:
+    - bundle exec rake test
+
+test-2.2.5:
+  image: ruby:2.2.5
+  script:
+    - bundle exec rake test
+
+test-2.2.4:
+  image: ruby:2.2.4
+  script:
+    - bundle exec rake test
+
+test-2.2.3:
+  image: ruby:2.2.3
+  script:
+    - bundle exec rake test
+
+test-2.2.2:
+  image: ruby:2.2.2
   script:
     - bundle exec rake test
 
 rubocop:
   script: