UserManagement : Update Keystone Container to use the latest

[rajat-soda]

Issue/Feature Description:
Update Keystone to use latest release (18.xx)
Sanity of existing Features after upgrade.

Why this issue to fixed / feature is needed(give scenarios or use cases):

How to reproduce, in case of a bug:

Other Notes / Environment Information: (Please give the env information, log link or any useful information for this issue)

Open Qs. : Do we migrate users from previous Releases.

[rajat-soda]

Updated the Key stone to use the "train" release of openstack.
Running into issues while updating docker container to Ubuntu18.04. Working on resolving this issue in installer.