Simplify taggings creation in specs

spec/factories/classifications.rb

@@ -9,6 +9,14 @@ FactoryBot.define do
     trait :milestone do
       kind { "milestone" }
     end
+
+    transient { taggables { [] } }
+
+    after(:create) do |tag, evaluator|
+      evaluator.taggables.each do |taggable|
+        create(:tagging, tag: tag, taggable: taggable)
+      end
+    end
   end
 
   factory :tagging, class: "ActsAsTaggableOn::Tagging" do

spec/models/tag_spec.rb

@@ -4,8 +4,7 @@ describe Tag do
 
   it "decreases tag_count when a debate is hidden" do
     debate = create(:debate)
-    tag = create(:tag)
+    tag = create(:tag, taggables: [debate])
-    tagging = create(:tagging, tag: tag, taggable: debate)
 
     expect(tag.taggings_count).to eq(1)
 
@@ -17,8 +16,7 @@ describe Tag do
 
   it "decreases tag_count when a proposal is hidden" do
     proposal = create(:proposal)
-    tag = create(:tag)
+    tag = create(:tag, taggables: [proposal])
-    tagging = create(:tagging, tag: tag, taggable: proposal)
 
     expect(tag.taggings_count).to eq(1)