specs: remove database_cleaner

This is not needed for integration tests since Rails 5.1.

See https://www.nicholasjacques.io/blog/you-probably-dont-need-databasecleaner/

Gemfile

@@ -90,7 +90,6 @@ group :test do
   gem 'capybara-email' # Access emails during integration tests
   gem 'capybara-screenshot' # Save a dump of the page when an integration test fails
   gem 'capybara-selenium'
-  gem 'database_cleaner'
   gem 'factory_bot'
   gem 'launchy'
   gem 'rails-controller-testing'

Gemfile.lock

@@ -189,12 +189,6 @@ GEM
     css_parser (1.9.0)
       addressable
     daemons (1.3.1)
-    database_cleaner (2.0.1)
-      database_cleaner-active_record (~> 2.0.0)
-    database_cleaner-active_record (2.0.0)
-      activerecord (>= 5.a)
-      database_cleaner-core (~> 2.0.0)
-    database_cleaner-core (2.0.1)
     datetime_picker_rails (0.0.7)
       momentjs-rails (>= 2.8.1)
     deep_cloneable (3.0.0)
@@ -804,7 +798,6 @@ DEPENDENCIES
   chunky_png
   clamav-client
   daemons
-  database_cleaner
   deep_cloneable
   delayed_cron_job
   delayed_job_active_record

spec/rails_helper.rb

@@ -58,7 +58,7 @@ RSpec.configure do |config|
   # If you're not using ActiveRecord, or you'd prefer not to run each of your
   # examples within a transaction, remove the following line or assign false
   # instead of true.
-  config.use_transactional_fixtures = false
+  config.use_transactional_fixtures = true
 
   # RSpec Rails can automatically mix in different behaviours to your tests
   # based on their file location, for example enabling you to call `get` and

spec/support/database_cleaner.rb

@@ -1,23 +0,0 @@
-RSpec.configure do |config|
-  expect_list = []
-
-  config.before(:suite) do
-    DatabaseCleaner.clean_with(:truncation, except: expect_list)
-  end
-
-  config.before(:each) do
-    DatabaseCleaner.strategy = :transaction
-  end
-
-  config.before(:each, js: true) do
-    DatabaseCleaner.strategy = :deletion, { except: expect_list }
-  end
-
-  config.before(:each) do
-    DatabaseCleaner.start
-  end
-
-  config.after(:each) do
-    DatabaseCleaner.clean
-  end
-end