Add a lock to storage upgrade and adjustment
Summary: Fixes T9715. Adds a MySQL-based lock to ensure that schema migrations are not applied on multiple hosts simultaneously.
Test Plan: Ran ./bin/storage upgrade concurrently. One invocation was successful whilst the other hit a PhutilLockException.
Reviewers: Blessed Reviewers, epriestley
Subscribers: Korvin
Maniphest Tasks: T9715
Differential Revision: https://secure.phabricator.com/D14463