.travis.yml in synchronised_migration-2.0.0 vs .travis.yml in synchronised_migration-2.1.0

@@ -1,3 +1,10 @@
----
 language: ruby
-script: bundle && bundle exec rspec
+rvm:
+  - 2.4
+  - 2.5
+  - 2.6
+script: bundle exec rspec
+sudo: false
+cache: bundler
+before_install:
+  - gem install bundler