Push: Bail out of notification job early if no subscriptions found
Push: Bail out of notification job early if no subscriptions found

Change-Id: Ica8e5c0496171dba4315c27072c2d865eb747e78

wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo