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