This is follow-up of 7eeb46e04d61189925dbbaa06d3016a0235d6200 and fixes
the following two points.
- tenant_name is deprecated but a proper warning message is missing
- password is deprecated and now is optional, but it is still
validated
Closes-Bug: #1973315
Change-Id: I169d42dee4896843e55d4989dc440ad7e7c7ec94