use config import for db setup

.travis.yml

@@ -2,6 +2,9 @@ language: ruby
 dist: trusty
 rvm: 2.4.2
 
+import:
+  - travis-ci/build-configs/db-setup.yml
+
 cache:
   bundler: true
 
@@ -20,6 +23,4 @@ env:
 
 before_install: gem install bundler
 
-before_script: bundle exec rake db:create --trace
-
 script: bundle exec rspec spec