Summary:
Ref T13043. After D18903, this data has migrated to shared infrastructure and has no remaining readers or writers.
Just delete it now, since the cost of a mistake here is very small (users need to "Forgot Password?" and pick a new password).
Test Plan: Grepped for `passwordHash`, `passwordSalt`, and variations.
Reviewers: amckinley
Reviewed By: amckinley
Maniphest Tasks: T13043
Differential Revision: https://secure.phabricator.com/D18904
