Fix old migrations failing because of new version of `strong_migratio…

…ns` (mastodon#10904)

db/migrate/20171005102658_create_account_moderation_notes.rb

@@ -8,6 +8,6 @@ def change
  t.timestamps
  end
 
- add_foreign_key :account_moderation_notes, :accounts, column: :target_account_id
+ safety_assured { add_foreign_key :account_moderation_notes, :accounts, column: :target_account_id }
  end
 end

db/migrate/20171010023049_add_foreign_key_to_account_moderation_notes.rb

@@ -1,5 +1,5 @@
 class AddForeignKeyToAccountModerationNotes < ActiveRecord::Migration[5.1]
  def change
- add_foreign_key :account_moderation_notes, :accounts
+ safety_assured { add_foreign_key :account_moderation_notes, :accounts }
  end
 end

db/migrate/20171118012443_add_moved_to_account_id_to_accounts.rb

@@ -1,6 +1,6 @@
 class AddMovedToAccountIdToAccounts < ActiveRecord::Migration[5.1]
  def change
  add_column :accounts, :moved_to_account_id, :bigint, null: true, default: nil
- add_foreign_key :accounts, :accounts, column: :moved_to_account_id, on_delete: :nullify
+ safety_assured { add_foreign_key :accounts, :accounts, column: :moved_to_account_id, on_delete: :nullify }
  end
 end