Remove duplicated test cases

The class ServersControllerCreateTest has the following duplicated
test cases since I091f14a9753059d759ba2f7b05ff33f5abea0f00 :

 * test_create_instance_with_config_drive_disabled
 * test_create_instance_local_href
 * test_create_instance_admin_pass_empty
 * test_create_instance_invalid_personality
 * test_create_location

This patch removes the duplicated test cases.
In addition, this removes the bookhref of test_create_location() also,
because it is not used.

Change-Id: I218d5ff443d4dbcec7520eab0b42e77fbd30eba8
Merge "Remove duplicated test cases"