As our internal QE reported to us, ddt is producing more consistent
names of the same tests with different variables then testscenarios.
With testscenarios it is something like:
foo_tempest_plugin.tests.something.SomeClass.test_foo[id-123456](c1,c2)
and with ddt is more similar to tests without scenarios:
foo_tempest_plugin.tests.something.SomeClass.test_foo_1[id-123456]
Apparently due to this inconsistency results of some tests couldn't be
properly reported properly to some tools which we are using downstream.
So this patch proposes to remove usage of testscenarios in
neutron_tempest_plugin and replace it with ddt where it is needed.
Actually ddt was already used in some of the tests here so this will
make it also more consistent across the tests in that repo.
Also as part of this effort I relalised that in some cases testscenarios
where used, tests were running e.g. 2 times but actually variable set to
different value in different scenarios were not used at all. So in such
case I simply dropped usage of testscenarios and left only one variant
of the test to be run.
Change-Id: Ieabab4ccaa0e2a365939425dff0c0776839251eb
ec162e0f56