Move property transaction construction to Almanac

Summary: Ref T7627. This centralizes this transaction construction code so the unit tests and Instances can both use it.

Test Plan: See D12116.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T7627

Differential Revision: https://secure.phabricator.com/D12118