Remove invalid design management version factory trait

spec/factories/design_management/versions.rb

@@ -13,11 +13,6 @@ FactoryBot.define do
       deleted_designs { [] }
     end
 
-    # Warning: this will intentionally result in an invalid version!
-    trait :empty do
-      designs_count { 0 }
-    end
-
     trait :importing do
       issue { nil }
 

spec/factories_spec.rb

@@ -13,7 +13,6 @@ RSpec.describe 'factories' do
       [:ci_job_artifact, :raw],
       [:ci_job_artifact, :gzip],
       [:ci_job_artifact, :correct_checksum],
-      [:design_version, :empty],
       [:environment, :non_playable],
       [:go_module_commit, :files],
       [:go_module_commit, :package],

spec/support/helpers/design_management_test_helpers.rb

@@ -35,7 +35,7 @@ module DesignManagementTestHelpers
 
   def act_on_designs(designs, &block)
     issue = designs.first.issue
-    version = build(:design_version, :empty, issue: issue).tap { |v| v.save!(validate: false) }
+    version = build(:design_version, designs_count: 0, issue: issue).tap { |v| v.save!(validate: false) }
     designs.each do |d|
       yield.create!(design: d, version: version)
     end