This patch removes a couple of tempest.conf settings that are being
overwrriten when Keystone is set to enforce scope.
These settings are already being set by the keystone devstack plugin [1]
and do not need to be overwritten here.
Keystone is changing the default admin credentials to be project-admin
instead of system-admin to address some failing tests in services that
require project-scoped admin for their admin APIs. [2] These overrides
are preventing that change from taking effect.
[1] https://opendev.org/openstack/keystone/src/branch/stable/2024.1/devstack/lib/scope.sh#L24-L25
[2] https://review.opendev.org/c/openstack/keystone/+/913999
Change-Id: I48edbcbaa993f2d1f35160c415986d21a15a4999