Remove 'parallel_test' gem

.travis.yml

@@ -42,8 +42,6 @@ before_script:
   - bundle install
   - bundle exec danger --verbose
   - bundle exec rake db:setup
-  - bundle exec rake parallel:create
-  - bundle exec rake parallel:prepare
   # Test coverage offered by Code Climate
   - curl -L https://codeclimate.com/downloads/test-reporter/test-reporter-latest-linux-amd64 > ./cc-test-reporter
   - chmod +x ./cc-test-reporter
@@ -53,7 +51,7 @@ before_script:
   - "/sbin/start-stop-daemon --start --quiet --pidfile /tmp/custom_xvfb_99.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :99 -ac -screen 0 1920x1080x16"
   - sleep 3 # give xvfb some time to start
 script:
-  - "export DISPLAY=:99.0 && RUBYOPT=W0 bundle exec parallel_rspec spec/$TESTFOLDER 2> /dev/null"
+  - "export DISPLAY=:99.0 && RUBYOPT=W0 bundle exec rspec spec/$TESTFOLDER 2> /dev/null"
 after_script:
   - 
   - ./cc-test-reporter format-coverage -t simplecov -o "coverage/codeclimate.$TESTFOLDER.json"

Gemfile

@@ -96,7 +96,6 @@ end
 
 group :development, :test do
   gem 'capybara'
-  gem 'parallel_tests'
   gem 'selenium-webdriver'
   gem 'simplecov', require: false
 end

Gemfile.lock

@@ -346,8 +346,6 @@ GEM
       activerecord (>= 4.2, < 5.2)
       request_store (~> 1.1)
     parallel (1.12.1)
-    parallel_tests (2.26.2)
-      parallel
     parser (2.4.0.2)
       ast (~> 2.3)
     powerpack (0.1.1)
@@ -627,7 +625,6 @@ DEPENDENCIES
   omniauth-google-oauth2
   open-uri-cached
   paper_trail
-  parallel_tests
   pragmatic_segmenter
   protected_attributes
   pry