Changes

PCU: TC_sns_del: use ascending transaction ids

The test case TC_sns_del is doing 2 SNS transactions.
One to prepare the test by changing the weight and a second
to do the deletion of a NSVC.

Do those 2 with ascending transaction ids.

Related: OS#6751
Change-Id: I3dfeb02673745f324fd70e5abf03eed7667789d0