Use plural fixture path

singular usage is deprecated

spec/rails_helper.rb

@@ -40,7 +40,7 @@
 
 RSpec.configure do |config|
   # Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
-  config.fixture_path = Rails.root.join('spec/fixtures').to_s
+  config.fixture_paths = [Rails.root.join('spec/fixtures')]
   # 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.