post-processor/atlas: adjust test for cross-platform filepath separator
post-processor/atlas: adjust test for cross-platform filepath separator

Make TestLongestCommonPrefix cross-platform friendly by defining
the test cases with filepath.Separator.

Fixes test failure on Windows.

rrva/packer,zeliff/packer,atlassian/packer,pearkes/packer,markpeek/packer,dantran/packer,jmptrader/packer,rk295/packer,youhong316/packer,bhcleek/packer,ldejager/packer,hashicorp/packer,jgkim/packer,quantang/packer,grubernaut/packer,pearkes/packer,monkeylittleinc/packer,ldejager/packer,legal90/packer,jonathankarsh/packer,icnocop/packer,paulvollmer/packer,c22/packer,yoctocloud/packer,jasonchaffee/packer,kpettijohn/packer,mafrosis/packer,mvanholsteijn/packer,blairham/packer,dantran/packer,blairham/packer,dieu/packer,jmptrader/packer,ricardclau/packer,KohlsTechnology/packer,ldejager/packer,dantran/packer,zhuzhih2017/packer,KohlsTechnology/packer,grange74/packer,sean-/packer,timsutton/packer,sequenceiq/packer,threatstream/packer,tas50/packer,mwhooker/packer,btd/packer,atlassian/packer,Sheile/packer,AlphaStaxLLC/packer,bensojona/packer,icnocop/packer,mafrosis/packer,dave2/packer,ChrisLundquist/packer,jae2/packer,p1-nico/packer,jonathankarsh/packer,yonglehou/packer,sneal/packer,mohae/packer,justincampbell/packer,grubernaut/packer,life360/packer,jonathankarsh/packer,feateds/packer,kpettijohn/packer,taliesins/packer,marklap/packer,hazelesque/packer,pvandervelde/packer,taliesins/packer,arizvisa/packer,atlassian/packer,esemplare/packer,gildas/packer-hyperv,dave2/packer,life360/packer,sgirones/packer,aneeshusa/packer,ricardclau/packer,rickard-von-essen/packer,manicai/packer,mwhooker/packer,pvanbuijtene/packer,zakuro9715/packer,pieter-lazzaro/packer,boumenot/packer,mkuzmin/packer,Cbeck527/packer,kpettijohn/packer,routelastresort/packer,BayanGroup/packer,timsutton/packer,taliesins/packer,bhcleek/packer,pvandervelde/packer,burnzy/packer,btd/packer,jen20/packer,aneeshusa/packer,justincampbell/packer,c22/packer,paulmey/packer,jen20/packer,gildas/packer-hyperv,zeliff/packer,hazelesque/packer,life360/packer,jarl-dk/packer,orivej/packer,atlassian/packer,Silver90/packer,mitchellh/packer,dieu/packer,ChrisLundquist/packer,esemplare/packer,hashicorp/packer,mwhooker/packer,bryson/packer,markpeek/packer,quantang/packer,ephemeralsnow/packer,jamesleech/packer,jasonchaffee/packer,BayanGroup/packer,paulvollmer/packer,fnoeding/packer,pieter-lazzaro/packer,visioncritical/packer,jae2/packer,monsterzz/packer,justincampbell/packer,sneal/packer,tb3088/packer,pieter-lazzaro/packer,avldya/packer,monsterzz/packer,p1-nico/packer,styro/packer,dayglojesus/packer,bensojona/packer,tb3088/packer,higebu/packer,pecigonzalo/packer,life360/packer,taliesins/packer,timsutton/packer,rickard-von-essen/packer,jamesleech/packer,legal90/packer,evertrue/packer,ttaylor249/packer,dev-head/packer,pecigonzalo/packer,danschaffer/packer,markpeek/packer,mansunkuo/packer,stagrlee/packer,masbog/packer,visioncritical/packer,smaato/packer,jimmythedog/packer,smaato/packer,ricardclau/packer,esemplare/packer,tomwilkie/packer,p1-nico/packer,boumenot/packer,rnaveiras/packer,mohae/packer,legal90/packer,samdunne/packer,masbog/packer,sgirones/packer,marklap/packer,markpeek/packer,oliviertremblay/packer,tsmolka/packer,bryson/packer,evertrue/packer,timsutton/packer,mayflower/packer,gbarberi/packer,hashicorp/packer,bryson/packer,beni55/packer,dev-head/packer,Akasurde/packer,israelshirk/packer,mwhooker/packer,rk295/packer,higebu/packer,yoctocloud/packer,paulmey/packer,mkuzmin/packer,jgkim/packer,mitchellh/packer,tas50/packer,avldya/packer,esemplare/packer,marc-ta/packer,sequenceiq/packer,israelshirk/packer,legal90/packer,bryson/packer,p1-nico/packer,paulmey/packer,sean-/packer,Cbeck527/packer,vtolstov/packer,mayflower/packer,arizvisa/packer,atlassian/packer,zhuzhih2017/packer,danschaffer/packer,Xiol/packer,manicai/packer,mgk/packer,rodm/packer,feateds/packer,yoctocloud/packer,sneal/packer,DualSpark/packer,c22/packer,mayflower/packer,tomwilkie/packer,mvanholsteijn/packer,jean/packer,AlphaStaxLLC/packer,sequenceiq/packer,mefellows/packer,jasonchaffee/packer,yonglehou/packer,markpeek/packer,fnoeding/packer,Silver90/packer,smaato/packer,zhuzhih2017/packer,trumant/packer,sean-/packer,mgk/packer,evertrue/packer,oliviertremblay/packer,bhcleek/packer,boumenot/packer,KFishner/packer,sobrinho/packer,markpeek/packer,dave2/packer,sgirones/packer,tomwilkie/packer,justincampbell/packer,jae2/packer,p1-nico/packer,blairham/packer,Sheile/packer,grange74/packer,ricardclau/packer,smaato/packer,napramirez/packer,ttaylor249/packer,pieter-lazzaro/packer,jen20/packer,Silver90/packer,btd/packer,jsternberg/packer,jimmythedog/packer,ChrisLundquist/packer,ephemeralsnow/packer,mkuzmin/packer,jarl-dk/packer,beni55/packer,leroux/packer,KohlsTechnology/packer,mvanholsteijn/packer,boumenot/packer,pearkes/packer,yonglehou/packer,orivej/packer,aneeshusa/packer,jgkim/packer,jasonchaffee/packer,kgrvamsi/packer,hazelesque/packer,paulvollmer/packer,KohlsTechnology/packer,higebu/packer,mefellows/packer,pvandervelde/packer,zakuro9715/packer,sneal/packer,dieu/packer,bensojona/packer,mitchellh/packer,c22/packer,KohlsTechnology/packer,jen20/packer,ldejager/packer,icnocop/packer,mefellows/packer,AlphaStaxLLC/packer,esemplare/packer,kgrvamsi/packer,sansb/packer,marc-ta/packer,youhong316/packer,pvandervelde/packer,BayanGroup/packer,rickard-von-essen/packer,marc-ta/packer,Xiol/packer,aneeshusa/packer,rrva/packer,sobrinho/packer,rk295/packer,fnoeding/packer,dayglojesus/packer,jonathankarsh/packer,youhong316/packer,danschaffer/packer,stagrlee/packer,mvanholsteijn/packer,gildas/packer-hyperv,samdunne/packer,ricardclau/packer,rodm/packer,pieter-lazzaro/packer,yoctocloud/packer,tsmolka/packer,beni55/packer,noplay/packer,pecigonzalo/packer,samdunne/packer,icnocop/packer,jamesleech/packer,life360/packer,danschaffer/packer,Silver90/packer,higebu/packer,LinusU/packer,trumant/packer,mgk/packer,KFishner/packer,KFishner/packer,Cbeck527/packer,styro/packer,KohlsTechnology/packer,jgkim/packer,Akasurde/packer,threatstream/packer,LinusU/packer,dantran/packer,orivej/packer,marklap/packer,visioncritical/packer,zhuzhih2017/packer,mwhooker/packer,eranchetz/packer,tsmolka/packer,arizvisa/packer,grange74/packer,dayglojesus/packer,sansb/packer,vtolstov/packer,trumant/packer,tomwilkie/packer,hasJackb/packer,jamesbishopp/packer,jmptrader/packer,jasonchaffee/packer,rickard-von-essen/packer,sobrinho/packer,hashicorp/packer,bryson/packer,mansunkuo/packer,leroux/packer,c22/packer,grubernaut/packer,grubernaut/packer,jean/packer,mohae/packer,yoctocloud/packer,ChrisLundquist/packer,dantran/packer,routelastresort/packer,LinusU/packer,ricardclau/packer,rodm/packer,BayanGroup/packer,taliesins/packer,Xiol/packer,grubernaut/packer,LinusU/packer,mkuzmin/packer,threatstream/packer,zeliff/packer,jen20/packer,gbarberi/packer,vtolstov/packer,sean-/packer,grange74/packer,dieu/packer,jmptrader/packer,jarl-dk/packer,sgirones/packer,mayflower/packer,pvanbuijtene/packer,jimmythedog/packer,jimmythedog/packer,danschaffer/packer,youhong316/packer,sean-/packer,fnoeding/packer,jsternberg/packer,rickard-von-essen/packer,dayglojesus/packer,mefellows/packer,routelastresort/packer,pieter-lazzaro/packer,c22/packer,sansb/packer,sneal/packer,pvanbuijtene/packer,timsutton/packer,quantang/packer,hasJackb/packer,smaato/packer,monsterzz/packer,avldya/packer,bradparks/packer__create_vm_for_aws_docker_vagrant_etc,bradparks/packer__create_vm_for_aws_docker_vagrant_etc,hasJackb/packer,dev-head/packer,dave2/packer,mansunkuo/packer,mayflower/packer,kgrvamsi/packer,pecigonzalo/packer,quantang/packer,manicai/packer,zakuro9715/packer,jamesbishopp/packer,mafrosis/packer,oliviertremblay/packer,monsterzz/packer,bensojona/packer,jen20/packer,youhong316/packer,mohae/packer,rodm/packer,noplay/packer,arizvisa/packer,monkeylittleinc/packer,vtolstov/packer,rnaveiras/packer,taliesins/packer,hazelesque/packer,beni55/packer,kpettijohn/packer,pvanbuijtene/packer,jamesleech/packer,timsutton/packer,tas50/packer,yonglehou/packer,grubernaut/packer,mafrosis/packer,manicai/packer,leroux/packer,noplay/packer,threatstream/packer,arizvisa/packer,zeliff/packer,tas50/packer,bryson/packer,marc-ta/packer,lantrix/packer,oliviertremblay/packer,DualSpark/packer,jae2/packer,ChrisLundquist/packer,paulmey/packer,evertrue/packer,feateds/packer,zhuzhih2017/packer,pearkes/packer,tsmolka/packer,lantrix/packer,p1-nico/packer,mitchellh/packer,styro/packer,AlphaStaxLLC/packer,rnaveiras/packer,arizvisa/packer,ttaylor249/packer,eranchetz/packer,jsternberg/packer,ephemeralsnow/packer,orivej/packer,ChrisLundquist/packer,tsmolka/packer,routelastresort/packer,jamesbishopp/packer,monkeylittleinc/packer,israelshirk/packer,burnzy/packer,bradparks/packer__create_vm_for_aws_docker_vagrant_etc,tb3088/packer,mansunkuo/packer,mkuzmin/packer,pvandervelde/packer,sean-/packer,quantang/packer,israelshirk/packer,mitchellh/packer,boumenot/packer,gildas/packer-hyperv,rnaveiras/packer,ttaylor249/packer,btd/packer,napramirez/packer,jarl-dk/packer,rk295/packer,dave2/packer,icnocop/packer,tb3088/packer,jean/packer,tsmolka/packer,ephemeralsnow/packer,pvanbuijtene/packer,Sheile/packer,mohae/packer,routelastresort/packer,jean/packer,smaato/packer,DualSpark/packer,zakuro9715/packer,monkeylittleinc/packer,gbarberi/packer,stagrlee/packer,samdunne/packer,legal90/packer,mgk/packer,Cbeck527/packer,jamesbishopp/packer,burnzy/packer,visioncritical/packer,rnaveiras/packer,Sheile/packer,dave2/packer,grange74/packer,stagrlee/packer,burnzy/packer,Akasurde/packer,masbog/packer,Akasurde/packer,threatstream/packer,hasJackb/packer,ephemeralsnow/packer,dayglojesus/packer,ttaylor249/packer,Xiol/packer,paulmey/packer,rnaveiras/packer,bhcleek/packer,mkuzmin/packer,atlassian/packer,bhcleek/packer,monkeylittleinc/packer,tb3088/packer,napramirez/packer,tas50/packer,noplay/packer,trumant/packer,sobrinho/packer,higebu/packer,bradparks/packer__create_vm_for_aws_docker_vagrant_etc,KFishner/packer,eranchetz/packer,blairham/packer,jimmythedog/packer,Cbeck527/packer,tb3088/packer,lantrix/packer,masbog/packer,feateds/packer,sansb/packer,dev-head/packer,styro/packer,jsternberg/packer,gbarberi/packer,pvandervelde/packer,marklap/packer,sequenceiq/packer,DualSpark/packer,Akasurde/packer,paulvollmer/packe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