libvirt: improve unit test time
libvirt: improve unit test time

A number of tests would invoke code that would sleep. This
patch adds a mocked function for the sleep.

Change-Id: Iecdc8488393cb118aa77bc5c33bcfde33ceb4733
Closes-bug: #1279820

yatinkumbhare/openstack-nova,felixma/nova,BeyondTheClouds/nova,phenoxim/nova,mikalstill/nova,mmnelemane/nova,leilihh/nova,mahak/nova,jianghuaw/nova,eayunstack/nova,JianyuWang/nova,ted-gould/nova,scripnichenko/nova,Stavitsky/nova,whitepages/nova,shail2810/nova,ewindisch/nova,jianghuaw/nova,cloudbase/nova-virtualbox,akash1808/nova_test_latest,kimjaejoong/nova,nikesh-mahalka/nova,jeffrey4l/nova,cernops/nova,barnsnake351/nova,rajalokan/nova,sebrandon1/nova,rahulunair/nova,zhimin711/nova,zhimin711/nova,iuliat/nova,devendermishrajio/nova,orbitfp7/nova,zzicewind/nova,apporc/nova,Stavitsky/nova,mandeepdhami/nova,yosshy/nova,silenceli/nova,leilihh/novaha,leilihh/novaha,Metaswitch/calico-nova,berrange/nova,BeyondTheClouds/nova,mgagne/nova,watonyweng/nova,viggates/nova,tianweizhang/nova,watonyweng/nova,phenoxim/nova,thomasem/nova,bgxavier/nova,ruslanloman/nova,gooddata/openstack-nova,saleemjaveds/https-github.com-openstack-nova,yatinkumbhare/openstack-nova,tianweizhang/nova,affo/nova,takeshineshiro/nova,cloudbase/nova,rajalokan/nova,j-carpentier/nova,tangfeixiong/nova,TwinkleChawla/nova,gooddata/openstack-nova,joker946/nova,Tehsmash/nova,mahak/nova,cyx1231st/nova,shahar-stratoscale/nova,hanlind/nova,tealover/nova,shahar-stratoscale/nova,sebrandon1/nova,tanglei528/nova,shail2810/nova,bigswitch/nova,kimjaejoong/nova,petrutlucian94/nova,dims/nova,mmnelemane/nova,eharney/nova,petrutlucian94/nova,j-carpentier/nova,CCI-MOC/nova,eharney/nova,cloudbase/nova,LoHChina/nova,openstack/nova,mandeepdhami/nova,Metaswitch/calico-nova,affo/nova,dawnpower/nova,cloudbase/nova-virtualbox,Tehsmash/nova,alexandrucoman/vbox-nova-driver,CEG-FYP-OpenStack/scheduler,TwinkleChawla/nova,luogangyi/bcec-nova,devendermishrajio/nova_test_latest,virtualopensystems/nova,adelina-t/nova,akash1808/nova,blueboxgroup/nova,eayunstack/nova,cernops/nova,angdraug/nova,double12gzh/nova,openstack/nova,NeCTAR-RC/nova,rahulunair/nova,ewindisch/nova,adelina-t/nova,fnordahl/nova,belmiromoreira/nova,redhat-openstack/nova,jeffrey4l/nova,cyx1231st/nova,devendermishrajio/nova,varunarya10/nova_test_latest,petrutlucian94/nova_dev,klmitch/nova,belmiromoreira/nova,BeyondTheClouds/nova,barnsnake351/nova,MountainWei/nova,whitepages/nova,alaski/nova,devendermishrajio/nova_test_latest,sebrandon1/nova,virtualopensystems/nova,CiscoSystems/nova,luogangyi/bcec-nova,takeshineshiro/nova,viggates/nova,bgxavier/nova,hanlind/nova,CCI-MOC/nova,dims/nova,saleemjaveds/https-github.com-openstack-nova,varunarya10/nova_test_latest,NeCTAR-RC/nova,isyippee/nova,badock/nova,tangfeixiong/nova,noironetworks/nova,Francis-Liu/animated-broccoli,CloudServer/nova,Juniper/nova,silenceli/nova,JioCloud/nova,edulramirez/nova,ted-gould/nova,openstack/nova,akash1808/nova,mikalstill/nova,projectcalico/calico-nova,tudorvio/nova,klmitch/nova,tudorvio/nova,LoHChina/nova,JioCloud/nova,Juniper/nova,spring-week-topos/nova-week,iuliat/nova,petrutlucian94/nova_dev,isyippee/nova,fnordahl/nova,jianghuaw/nova,gooddata/openstack-nova,mahak/nova,maelnor/nova,rahulunair/nova,CloudServer/nova,zaina/nova,eonpatapon/nova,Yusuke1987/openstack_template,yosshy/nova,Juniper/nova,klmitch/nova,zzicewind/nova,Yusuke1987/openstack_template,ruslanloman/nova,badock/nova,alexandrucoman/vbox-nova-driver,mgagne/nova,vmturbo/nova,vladikr/nova_drafts,mikalstill/nova,gooddata/openstack-nova,zaina/nova,CiscoSystems/nova,jianghuaw/nova,cernops/nova,blueboxgroup/nova,vmturbo/nova,raildo/nova,rrader/nova-docker-plugin,orbitfp7/nova,joker946/nova,double12gzh/nova,JioCloud/nova_test_latest,nikesh-mahalka/nova,alvarolopez/nova,JianyuWang/nova,rrader/nova-docker-plugin,rajalokan/nova,projectcalico/calico-nova,Juniper/nova,dawnpower/nova,akash1808/nova_test_latest,rajalokan/nova,tanglei528/nova,cloudbase/nova,CEG-FYP-OpenStack/scheduler,tealover/nova,edulramirez/nova,leilihh/nova,MountainWei/nova,bigswitch/nova,maelnor/nova,alaski/nova,redhat-openstack/nova,apporc/nova,klmitch/nova,angdraug/nova,hanlind/nova,JioCloud/nova_test_latest,raildo/nova,vmturbo/nova,vmturbo/nova,felixma/nova,alvarolopez/nova,Francis-Liu/animated-broccoli,eonpatapon/nova,berrange/nova,scripnichenko/nova,spring-week-topos/nova-week,noironetworks/nova,vladikr/nova_drafts,thomasem/nova