R1:d98c47041f13

PHP 8.2: fix deprecated creation of dynamic properties

Summary:
This change fixes a typo that, in PHP 8.2, causes this exception:

Creation of dynamic property PhabricatorAuthPasswordException::$confirmError is deprecated

Closes T15201

Test Plan: - I checked that "error" was spelled with two "r"

Reviewers: O1 Blessed Committers, avivey

Reviewed By: O1 Blessed Committers, avivey

Subscribers: speck, tobiaswiese, Matthew, Cigaryno

Maniphest Tasks: T15201

Differential Revision: https://we.phorge.