[ostf] Check stack rollback

[Dmitry Belyaninov]

Detailed bug description:
SWARM test failed with error:
Failed 1 OSTF tests; should fail 0 tests. Names of failed tests:
  - Check stack rollback (error)

https://product-ci.infra.mirantis.net/job/9.x.system_test.ubuntu.multiracks_2/58/testReport/(root)/two_nodegroups_network_templates/two_nodegroups_network_templates/

Steps to reproduce:
run the test
Expected results:
pass
Actual result:
fail
Reproducibility:
 <put your information here>
Workaround:
 <put your information here>
Impact:
 <put your information here>
Description of the environment:
 Operation system: <put your information here>
 Versions of components: <put your information here>
 Reference architecture: <put your information here>
 Network model: <put your information here>
 Related projects installed: <put your information here>
Additional information:
 <put your information here>

[Maksim Malchuk (mmalchuk)]

please provide the version of the 9.x snapshot used. if it #251 this bug can be closed as a duplicate because snapshot #251 contain bad mysql-wsrep version and doesn't contain bugfix for nailgun due to recent merge fail.

[Stanislaw Bogatkin (sbogatkin)]

Closed as invalid due to inactivity more than one month.