[lib] Clear all holders on logout

Summary:
Created a hook that removes all holders from holder store, using the "process holders" action.
Called the hook in useLogOut() which is called for all logout actions (identity v1, legacy, primary/secondary).

Depends on D13411

Test Plan: Established a few holders, then logged out. Verified that Blob Service was called

Reviewers: kamil, tomek

Reviewed By: kamil

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D13416