[identity] Reword warns about device list out of sync

Summary:
Now, not only Identity Service can update device lists, but also QR Auth, secondary device logout etc.
So these messages are out of date because this can happen in a normal scenario during primary <-> secondary device talk.

Reworded and lowered log levels to avoid unnecessarily triggering AWS alerts.

Test Plan: Enabled logging in unit tests and ran them. They cover all scenarios of calling this func.

Reviewers: will

Reviewed By: will

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D12268