Add: #667 プレビューカード、参照のフェッチを行わないドメインの設定 (#690)

app/models/form/admin_settings.rb

@@ -63,6 +63,8 @@ class Form::AdminSettings
     emoji_reaction_disallow_domains
     block_unfollow_account_mention
     hold_remote_new_accounts
+    stop_fetch_activity_domains
+    stop_link_preview_domains
   ).freeze
 
   INTEGER_KEYS = %i(
@@ -120,6 +122,8 @@ class Form::AdminSettings
 
   STRING_ARRAY_KEYS = %i(
     emoji_reaction_disallow_domains
+    stop_fetch_activity_domains
+    stop_link_preview_domains
   ).freeze
 
   attr_accessor(*KEYS)