[services] Tests - Add byte size crate

Summary:
Depends on D4166

Adding bytesize crate

Test Plan: None, this is not used yet, the project can still be built.

Reviewers: palys-swm, varun, geekbrother, ashoat

Reviewed By: palys-swm, varun

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

Differential Revision: https://phab.comm.dev/D4227