BUG-692 Fix intermittent failure in NetconfDeviceTest

Error in NetconfDeviceTest.testNotificationBeforeSchema, verification without timeout was performed before the actual call.

Fixed by adding timeout to all verifications.

Change-Id: I494523036fff456d66398f0d17b0003fe6c083a0
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>
Merge "BUG-692 Fix intermittent failure in NetconfDeviceTest"