[services] Backup - Implement generating holder

Summary:
Depends on D4029

https://linear.app/comm/issue/ENG-1128/implement-generating-holders

Test Plan: Services still build

Reviewers: palys-swm

Reviewed By: palys-swm

Subscribers: ashoat, palys-swm, Adrian, atul, yayabosh

Differential Revision: https://phabricator.ashoat.com/D4030