[lib] Add functions to perform Blob Service holder actions

Summary:
Added function that perform Blob Service calls for adding/removing holders. Used input/output format compatible with action introduced in D13408
This can be simplified when batch endpoints are implemented for holders on Blob service.

Depends on D13408

Test Plan: Tested together with the next diff.

Reviewers: kamil, tomek

Reviewed By: kamil

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D13409