Allow the notifications from Aphlict debug messages to expire.

Summary: Currently, debugging (log) messages from the Aphlict client trigger a visible notification in the web UI (when `notification.debug` is enabled). After D9327, the log messages can be quite verbose and seem to "block" legitimate notifications because they are not automatically dismissed.

Test Plan: Enabled `notification.debug` and observed that the debugging notifications expired and closed after a few seconds.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9339