Remove redundant setup_client method

Those clients are already initialized in BaseV2ComputeTest class
BaseV2ComputeAdminTest class.
In addition, it is more clear to use the original client name.
The client name 'client' is too much general compare to 'flavors_client'
and 'admin_flavors_client'.

Change-Id: Ifbd687a7c1c99ff4652c7596d85eda404a3120ae
6 files changed