YouTube の自動同期 (#314) (#340)

#314

#314

#314

#314

#314

Co-authored-by: miteruzo <miteruzo@naver.com>
Reviewed-on: #340

backend/app/models/tag.rb

@@ -84,6 +84,7 @@ class Tag < ApplicationRecord
   def self.no_deerjikist = find_or_create_by_tag_name!('ニジラー情報不詳', category: :meta)
   def self.video = find_or_create_by_tag_name!('動画', category: :meta)
   def self.niconico = find_or_create_by_tag_name!('ニコニコ', category: :meta)
+  def self.youtube = find_or_create_by_tag_name!('YouTube', category: :meta)
 
   def self.normalise_tags tag_names, with_tagme: true,
                                      with_no_deerjikist: true,