R1:aca0f642a3bd

Add a "bin/audit synchronize" command

Summary: Ref T10978. This is just a maintenance convenience script. It can fix up overall commit state after you `bin/audit delete` stuff or nuke a bunch of stuff from the database, as I did on `secure.phabricator.com`.

Test Plan: Ran `bin/audit synchronize`, and `bin/audit update-owners`.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10978

Differential Revision: https://secure.phabricator.com/D17271