多言語化の基盤作り (#55) (#421)

Reviewed-on: #421
Co-authored-by: miteruzo <miteruzo@naver.com>

backend/spec/models/post_version_spec.rb

@@ -1,8 +1,8 @@
 require 'rails_helper'
 
 RSpec.describe PostVersion, type: :model do
-  let!(:tag_name) { TagName.create!(name: 'post_version_spec_tag') }
-  let!(:tag) { Tag.create!(tag_name: tag_name, category: :general) }
+  let!(:tag_name) { create(:tag_name, name: 'post_version_spec_tag') }
+  let!(:tag) { create(:tag, primary_tag_name: tag_name, category: :general) }
 
   let!(:post_record) do
     Post.create!(title: 'spec post', url: 'https://example.com/post-version-spec').tap do |post|