[services] Cargo.lock for feature-flags needs to be updated

Summary: Git commands cause feature-flags Cargo.lock to update. This means that its Cargo.lock must be updated to reflect feature-flags' current state.

Test Plan: Successfully built feature-flags

Reviewers: varun

Reviewed By: varun

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D10513