Fix incorrect assumption in TestAPISwarmRaftQuorum
Fix incorrect assumption in TestAPISwarmRaftQuorum

This test shuts down two out of three managers and then asserts that the
swarm has a leader. A swarm that lost quorum won't necessarily have a
leader, and in this case only has one because the old leader is still
around. Soon SwarmKit will be changed so the leader gives up leadership
when quorum is lost. This will avoid confusing situations, like
read-only APIs succeeding, while ones that write to Raft hang.

Signed-off-by: Aaron Lehmann <8ecfc6017a87905413dcd7d63696a2a4c351b604@docker.com>

mike1729/docker,miminar/docker,trebonian/docker,bearstech/moby,srust/docker,haveatry/docker,paralin/docker,shishir-a412ed/docker,laijs/moby,mtesselH/docker,Mokolea/docker,AkihiroSuda/docker,pramodhkp/moby,justincormack/docker,sarnautov/moby,moul/docker,rhatdan/docker,noironetworks/docker,ColinHebert/docker,KarthikNayak/docker,kencochrane/docker,tonistiigi/docker,prertik/docker,bonczj/moby-json-file-logger,maxamillion/docker,laijs/docker,amatsus/docker,jvanz/docker,liaoqingwei/docker,dccurtis/docker,paralin/docker,scotttlin/docker,sdurrheimer/docker,mike1729/docker,miminar/docker,kojiromike/docker,ColinHebert/docker,SvenDowideit/docker,hqhq/moby,charleszheng44/moby,tklauser/docker,mixja/docker,ibuildthecloud/docker,gschaetz/moby,dmcgowan/docker,mahak/docker,yongtang/docker,tophj-ibm/moby,laijs/moby,dperny/docker,raja-sami-10p/moby,bearstech/moby,kolyshkin/moby,justincormack/docker,unclejack/docker,crosbymichael/docker,flavio/docker,jthelin/docker,imkin/moby,KingEmet/docker,KingEmet/docker,jlhawn/docker,Mokolea/docker,kencochrane/docker,nawawi/docker,konstruktoid/docker-1,resin-io/docker,Ramzec/docker,dims/docker,imkin/moby,unclejack/docker,flavio/docker,mtesselH/docker,coreos/docker,unclejack/docker,gjaskiewicz/moby,danyalKhaliq10p/moby,moby/moby,hqhq/moby,x1022as/docker,moby/moby,prertik/docker,vdemeester/docker,tophj-ibm/docker,paralin/docker,bonczj/moby-json-file-logger,mtesselH/docker,kojiromike/docker,jimjag/docker,nawawi/docker,flavio/docker,tmp6154/docker,nawawi/docker,konstruktoid/docker-upstream,tmp6154/docker,yosifkit/docker,yasiramin10p/moby,cpuguy83/docker,cpuguy83/docker,raja-sami-10p/moby,duglin/docker,ndeloof/docker,YuPengZTE/docker,pramodhkp/moby,kolyshkin/moby,johnstep/moby-moby,Ramzec/docker,danyalKhaliq10p/moby,PatrickLang/moby,YuPengZTE/docker,shishir-a412ed/docker,charleszheng44/moby,konstruktoid/docker-1,konstruktoid/docker-1,djs55/docker,trebonian/docker,ibuildthecloud/docker,ibuildthecloud/docker,jwhonce/docker,mahak/docker,dperny/docker,tonistiigi/docker,fcrisciani/docker,rremer/moby,ripcurld0/moby,danyalKhaliq10p/moby,ibuildthecloud/docker,jvanz/docker,mikebrow/docker,allencloud/docker,gjaskiewicz/moby,bearstech/moby,mkumatag/docker,pradipd/moby,gschaetz/moby,mahak/docker,kolyshkin/docker,paralin/docker,sterchelen/docker,docker/docker,Mokolea/docker,jwhonce/docker,tklauser/docker,konstruktoid/docker-upstream,thaJeztah/docker,nalind/docker,tophj-ibm/docker,KarthikNayak/docker,johnstep/moby-moby,sdurrheimer/docker,KingEmet/docker,KarthikNayak/docker,thaJeztah/docker,dsheets/moby,ripcurld0/moby,dmcgowan/docker,vdemeester/docker,gschaetz/moby,ibuildthecloud/docker,tophj-ibm/docker,mixja/docker,lixiaobing1/docker,haveatry/docker,ndeloof/docker,Ramzec/docker,cyphar/docker,jimjag/docker,cyphar/docker,cyphar/docker,maxamillion/docker,shhsu/docker,haveatry/docker,shhsu/docker,PatrickLang/moby,mike1729/docker,duglin/docker,lixiaobing1/docker,scotttlin/docker,dims/docker,scotttlin/docker,SvenDowideit/docker,jvanz/docker,jameszhan/docker,resin-io/docker,jimjag/docker,mikebrow/docker,flavio/docker,Ramzec/docker,kolyshkin/docker,nalind/docker,rancher/docker,kolyshkin/moby,rancher/docker,gjaskiewicz/moby,estesp/docker,allencloud/docker,gnailuy/docker,cpuguy83/docker,bonczj/moby-json-file-logger,nawawi/docker,yasiramin10p/moby,gnailuy/docker,tophj-ibm/moby,yosifkit/docker,hqhq/moby,shishir-a412ed/docker,moby/moby,moul/docker,ndeloof/docker,crosbymichael/docker,duglin/docker,madhanrm/docker,naveed-jamil-tenpearls/moby,pradipd/moby,resin-io/docker,kojiromike/docker,coolljt0725/docker,prertik/docker,JMesser81/docker,tianon/docker,coolljt0725/docker,sterchelen/docker,tophj-ibm/moby,POLJM242/docker,djs55/docker,dsheets/moby,ColinHebert/docker,SvenDowideit/docker,dperny/docker,mkumatag/docker,yummypeng/docker,crosbymichael/docker,JMesser81/docker,coreos/docker,naveed-jamil-tenpearls/moby,charleszheng44/moby,estesp/docker,sdurrheimer/docker,AkihiroSuda/docker,nalind/docker,shhsu/docker,Mokolea/docker,tklauser/docker,raja-sami-10p/moby,whuwxl/docker,johnstep/moby-moby,yummypeng/docker,yosifkit/docker,naveed-jamil-tenpearls/moby,noironetworks/docker,tonistiigi/docker,jameszhan/docker,moul/docker,mahak/docker,moul/docker,x1022as/docker,sarnautov/moby,lixiaobing1/docker,dims/docker,x1022as/docker,amatsus/docker,coolljt0725/docker,jimjag/docker,lixiaobing10051267/docker,moby/moby,lixiaobing10051267/docker,djs55/docker,konstruktoid/docker-upstream,YuPengZTE/docker,gnailuy/docker,ripcurld0/moby,jlhawn/docker,JMesser81/docker,bearstech/moby,yongtang/docker,whuwxl/docker,justincormack/docker,liaoqingwei/docker,thaJeztah/docker,rhatdan/docker,imkin/moby,noironetworks/docker,docker/docker,madhanrm/docker,kencochrane/docker,AkihiroSuda/docker,liaoqingwei/docker,mkumatag/docker,jameszhan/docker,dccurtis/docker,rancher/docker,trebonian/docker,rremer/moby,tianon/docker,laijs/docker,sterchelen/docker,fcrisciani/docker,whuwxl/docker,thaJeztah/docker,lixiaobing10051267/docker,pramodhkp/moby,allencloud/docker,srust/docker,miminar/docker,jwhonce/docker,maxamillion/docker,pradipd/moby,jthelin/docker,trebonian/docker,nalind/docker,gnailuy/docker,yasiramin10p/moby,amatsus/docker,rhatdan/docker,dccurtis/docker,konstruktoid/docker-upstream,dsheets/moby,vdemeester/docker,mikebrow/docker,sarnautov/moby,PatrickLang/moby,coreos/docker,yosifkit/docker,jlhawn/docker,docker/docker,AkihiroSuda/docker,cpuguy83/docker,tmp6154/docker,mixja/docker,rremer/moby,madhanrm/docker,estesp/docker,yongtang/docker,dmcgowan/docker,laijs/moby,yummypeng/docker,srust/docker,fcrisciani/docker,laijs/docker,POLJM242/docker