Directly delete the "organization is invalid" error

We were getting a warning since upgrading to Rails 6.1:

DEPRECATION WARNING: Calling `delete` to an ActiveModel::Errors messages
hash is deprecated. Please call `ActiveModel::Errors#delete` instead.

So we're deleting the error instead of deleting the message.

app/controllers/account_controller.rb

@@ -10,7 +10,7 @@ def update
  if @account.update(account_params)
  redirect_to account_path, notice: t("flash.actions.save_changes.notice")
  else
- @account.errors.messages.delete(:organization)
+ @account.errors.delete(:organization)
  render :show
  end
  end

app/controllers/organizations/registrations_controller.rb

@@ -13,7 +13,7 @@ def create
  if resource.valid?
  super do |user|
  # Removes unuseful "organization is invalid" error message
- user.errors.messages.delete(:organization)
+ user.errors.delete(:organization)
  end
  else
  render :new