Fix typo in swift/test/unit/account/test_backend.py
Fix typo in swift/test/unit/account/test_backend.py

Change-Id: I6cab110599019471b4005f1584fc26fa2a85d02e

hurricanerix/swift,takeshineshiro/swift,matthewoliver/swift,swiftstack/swift,rackerlabs/swift,matthewoliver/swift,bkolli/swift,matthewoliver/swift,daasbank/swift,gold3bear/swift,levythu/swift,mjzmjz/swift,smerritt/swift,psachin/swift,hbhdytf/mac2,zackmdavis/swift,tipabu/swift,notmyname/swift,smerritt/swift,prashanthpai/swift,maginatics/swift,bouncestorage/swift,bradleypj823/swift,aerwin3/swift,larsbutler/swift,shibaniahegde/OpenStak_swift,clayg/swift,notmyname/swift,Em-Pan/swift,wenhuizhang/swift,openstack/swift,hbhdytf/mac2,hbhdytf/mac2,clayg/swift,mjwtom/swift,nadeemsyed/swift,tipabu/swift,williamthegrey/swift,Em-Pan/swift,mjzmjz/swift,dencaval/swift,daasbank/swift,Seagate/swift,wenhuizhang/swift,smerritt/swift,bradleypj823/swift,thiagodasilva/swift,tipabu/swift,AfonsoFGarcia/swift,bouncestorage/swift,AfonsoFGarcia/swift,redbo/swift,redhat-openstack/swift,hurricanerix/swift,matthewoliver/swift,bkolli/swift,hbhdytf/mac,Akanoa/swift,levythu/swift,psachin/swift,gold3bear/swift,hbhdytf/mac2,clayg/swift,swiftstack/swift,notmyname/swift,maginatics/swift,openstack/swift,Seagate/swift,mjwtom/swift,psachin/swift,IPVL/swift-kilo,redhat-openstack/swift,swiftstack/swift,larsbutler/swift,notmyname/swift,nadeemsyed/swift,prashanthpai/swift,Akanoa/swift,clayg/swift,revoer/keystone-8.0.0,redbo/swift,iostackproject/IO-Bandwidth-Differentiation,shibaniahegde/OpenStak_swift,nadeemsyed/swift,tipabu/swift,hurricanerix/swift,psachin/swift,revoer/keystone-8.0.0,zackmdavis/swift,hurricanerix/swift,hbhdytf/mac,openstack/swift,takeshineshiro/swift,IPVL/swift-kilo,thiagodasilva/swift,aerwin3/swift,iostackproject/IO-Bandwidth-Differentiation,nadeemsyed/swift,rackerlabs/swift,dencaval/swift,smerritt/swift,williamthegrey/swift,openstack/swift