[services] Backup - pull backup - change tests

Summary:
Depends on D4598

Test all the changes from the last 3 diffs.

Test Plan:

cd services
yarn run-blob-service-in-sandbox
yarn run-backup-service-in-sandbox

yarn run-integration-tests backup

Reviewers: tomek

Reviewed By: tomek

Subscribers: ashoat, tomek, adrian, atul, abosh

Differential Revision: https://phab.comm.dev/D4556