This commit adds role assignment test coverage for users who have the
admin role assigned on the system.
Subsequent patches will:
- add functionality for domain readers
- add functionality for domain members
- add functionality for domain admins
- add functionality for project readers
- add functionality for project members
- add functionality for project admins
- remove the obsolete policies from policy.v3cloudsample.json
Change-Id: If0d418a7117623b3bfe11b8e23781d02ac1debf0
Partial-Bug: 1750673
Closes-Bug: 1816833