Don't disable apps on update if PHP >= 7.0.0

When PHP in a version higher than 7.0.0 is used we catch fatal exceptions in app.php and gracefully already disable the app. There is thus no need to also disable the apps on updates.

This has been requested by Jan to fix because that is "the most annoying thing ever" :TM:. – I'd say we give it a try and if that causes problems in the future we can consider alternative approaches.

Signed-off-by: Lukas Reschke <lukas@statuscode.ch>