Use GlobalDBSingleton when touching database from the native iOS code.
Summary: This differential replaces any direct database access in iOS native code with GlobalDBSingleton API
Test Plan: Creating test release with those changes would remove iOS 137 crash
Reviewers: tomek, atul, jon
Reviewed By: tomek, jon
Subscribers: ashoat, abosh
Differential Revision: https://phab.comm.dev/D5234