Enable App Groups in Comm and Notification Service

Summary: This diffs enables usage of App Groups in NotificationService and Comm so that they can securely share files - e.g. SQlite Database

Test Plan: Not testing plan for this diff. Its child will introduce functions that use App groups to share SQLite database between NotificationService and Comm that will have testing plan.

Reviewers: palys-swm, karol-bisztyga, ashoat

Reviewed By: palys-swm, ashoat

Subscribers: ashoat, Adrian, atul, yayabosh

Differential Revision: https://phabricator.ashoat.com/D3992