ns: test if SNS fails when all signalling NSVCs failes

As 3GPP TS 48.016 ยง 7.4b.1.1 specifies this behaviour.
1. do success SNS configuration
2. change sig weight of the seconds inactive bind
3. add second bind to SNS
4. stop reacting to NS_ALIVE on first NSVC (only NSVC with sig weight)
5. expect SNS SIZE

Related: OS#5039
Change-Id: Id06e34e7235d94a06152a0015487a507d6492a97
1 file changed