This patch removes the copy of tempest scenario manager
and directly imports the manager from tempest which has been
marked stable in tempest 27.0.0 release.
Change-Id: I403d5bc2eef464e6071e466aeab8e040b9055568
This tempest plugin is being split out of the main keystone project in
accordance with Queens goal "Split Tempest Plugins into Separate
Repos/Projects"[1]. This patch applies the standard boilerplate files
for OpenStack projects so that it can stand on its own.
[1] https://governance.openstack.org/tc/goals/queens/split-tempest-plugins.html