benchmark: rename argument to `count'
benchmark: rename argument to `count'

Change-Id: I7c9dbf97109dfc96e82a6d90b74d901e2fc33bac

chungg/python-aodhclient,gnocchixyz/python-gnocchiclient,chungg/python-aodhclient,sileht/python-gnocchiclient,openstack/python-aodhclient,gnocchixyz/python-gnocchiclient