#84 構文エラー修正

backend/app/models/tag.rb

@@ -1,6 +1,6 @@
 class Tag < ApplicationRecord
   has_many :post_tags, dependent: :delete_all, inverse_of: :tag
-  has_many :active_post_tags, -> { kept }, class_name: 'PostTag', :inverse_of: :tag
+  has_many :active_post_tags, -> { kept }, class_name: 'PostTag', inverse_of: :tag
   has_many :post_tags_with_discarded, -> { with_discarded }, class_name: 'PostTag'
   has_many :posts, through: :active_post_tags
   has_many :tag_aliases, dependent: :destroy