services: notifier: use new health uri

no idea why notifier does not use API.

URI of health servlet was modified, we need to use the new one.

Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=961677
Change-Id: I5747c1137cd8d0b4c5e89f82d772526103ce8dc5
Signed-off-by: Alon Bar-Lev <alonbl@redhat.com>