use contrail admin for neutron+OC

Use a dedicated contrail user/password in
admin tenant for contrail.

Depends-On: https://gerrit.mcp.mirantis.com/#/c/33257

PROD-23357

Change-Id: I4090cfaa6c8c5398ec9ad2ea17307b5e95723595
(cherry picked from commit acaecb73ccc4b62e4e04fd3b4aacaf41f13e0307)
2 files changed