integration: wait all test processes
integration: wait all test processes

Otherwise a container cannot be destroyed and we will get an error
in the next case:
go test -v .
=== RUN TestExecPS
--- FAIL: TestExecPS (0.02s)
        exec_test.go:43: <nil>: [0] Id already in use: Container with id exists: testCT

Signed-off-by: Andrey Vagin <74c05afa918858348d6db8037d82fa8124870113@openvz.org>

xiaochenshen/runc,HuKeping/runc,clnperez/runc,tangkun75/libcontainer,shishir-a412ed/runc,ZJU-SEL/runc,kimh/runc,calavera/runc,cyphar/runc,balajibr/runc,whuwxl/libcontainer,ZJU-SEL/runc,gitido/runc,estesp/libcontainer,jwuwork/runc,sunyuan3/runc,laijs/runc,boucher/runc,Microsoft/libcontainer,vbatts/runc,crosbymichael/libcontainer,BrickXu/libcontainer,mYmNeo/runc,shishir-a412ed/runc,sunyuan3/runc,han-wang/runc,mapk0y/runc,zhangyancoder/libcontainer,maxamillion/runc,ekuric/runc,haijunTan/runc,wking/runc,whosthatknocking/runc,dqminh/libcontainer,adrianreber/runc,InformatiQ/runc,docker/runc,hxfeng/runc,keloyang/libcontainer,rhatdan/runc,rsampaio/runc,gitido/runc,HardikDR/runc,coolljt0725/runc,ycaihua/runc,YujiOshima/runc,estesp/runc,ChengTiesheng/runc,carlye566/runc,vbatts/runc,hqhq/runc,sallyom/runc,estesp/libcontainer,w4ngyi/libcontainer,lizf-os/runc,ddnbgroup/runc,zenlinTechnofreak/runc,dqminh/libcontainer,calavera/runc,zhangyancoder/libcontainer,hqhq/libcontainer,chenchun/runc,ycaihua/libcontainer,InformatiQ/runc,crosbymichael/libcontainer,adrianreber/runc,coolljt0725/runc,aidanhs/runc,rootfs/runc,LK4D4/runc,stefanberger/runc,intfrr/runc,jhjeong-kr/runc,rootfs/runc,keloyang/libcontainer,keloyang/libcontainer,dqminh/libcontainer,tangkun75/libcontainer,axsh/runc,aidanhs/runc,jhjeong-kr/runc,willmtemple/runc,intfrr/runc,whosthatknocking/runc,lizf-os/runc,rhatdan/runc,axsh/runc,rsampaio/runc,carlye566/runc,talwai/runc,mheon/runc,kolyshkin/runc,rhatdan/libcontainer,runcom/runc,gitido/runc,jhowardmsft/runc,estesp/runc,mapk0y/runc,inatatsu/runc,meihuabo/runc,estesp/libcontainer,booyaa/runc,ycaihua/runc,laijs/runc,BrickXu/libcontainer,shenxiaochen/libcontainer,aidanhs/runc,mikebrow/runc,booyaa/runc,tangkun75/libcontainer,wcwxyz/runc,liuwharton/runc,rhatdan/libcontainer,mrunalp/runc,wking/runc,adrianreber/runc,boucher/runc,vbatts/runc,wangkirin/runc,Microsoft/libcontainer,ChengTiesheng/runc,stefanberger/runc,nkwilson/runc,ycaihua/runc,rsampaio/runc,dieface/runc,runcom/runc,mrunalp/runc,lizf-os/runc,sunyuan3/runc,estesp/runc,avagin/runc,dieface/runc,cxxly/runc,gwoo/runc,laijs/runc,thaJeztah/libcontainer,rhatdan/runc,keloyang/runc,wangkirin/runc,dqminh/runc,LTD-Beget/libcontainer,wangkirin/runc,balajibr/runc,meihuabo/runc,ChengTiesheng/runc,subuser-security/runc,liuwharton/runc,sallyom/runc,ddnbgroup/runc,cxxly/runc,docker/runc,ddnbgroup/runc,YujiOshima/runc,opencontainers/runc,LK4D4/runc,thaJeztah/libcontainer,w4ngyi/libcontainer,han-wang/runc,rootfs/runc,HardikDR/runc,docker/libcontainer,dqminh/runc,marcosnils/runc,albertoleal/runc,booyaa/runc,jwuwork/runc,YujiOshima/runc,mheon/runc,opencontainers/runc,marcosnils/runc,talwai/runc,rajasec/runc,HuKeping/runc,whuwxl/libcontainer,haijunTan/runc,willmtemple/runc,sallyom/runc,wking/runc,cxxly/runc,hxfeng/runc,fabiokung/runc,thaJeztah/libcontainer,shenxiaochen/libcontainer,runcom/libcontainer,abduld/runc,clnperez/runc,stefanberger/runc,kimh/runc,mikebrow/runc,dqminh/runc,docker/libcontainer,runcom/libcontainer,inatatsu/runc,liuwharton/runc,crosbymichael/libcontainer,ycaihua/libcontainer,subuser-security/runc,kolyshkin/runc,kimh/runc,cloudfoundry-incubator/runc,LK4D4/runc,Microsoft/libcontainer,zenlinTechnofreak/runc,coolljt0725/runc,nkwilson/runc,avagin/runc,navidshaikh/runc,whuwxl/libcontainer,dqminh/runc,inatatsu/runc,docker/libcontainer,justincormack/runc,HuKeping/runc,BrickXu/libcontainer,clnperez/runc,cloudfoundry-incubator/runc,chenchun/runc,maxamillion/runc,fabiokung/runc,rhatdan/runc,jhowardmsft/runc,hqhq/libcontainer,albertoleal/runc,nkwilson/runc,calavera/runc,navidshaikh/runc,hqhq/runc,ekuric/runc,haijunTan/runc,mikebrow/runc,LTD-Beget/libcontainer,markllama/runc,dieface/runc,cyphar/runc,crosbymichael/runc,marcosnils/runc,justincormack/runc,justincormack/runc,abduld/runc,keloyang/libcontainer,rhatdan/libcontainer,hxfeng/runc,cloudfoundry-incubator/runc,HardikDR/runc,kolyshkin/runc,shenxiaochen/libcontainer,chenchun/runc,navidshaikh/runc,LTD-Beget/libcontainer,axsh/runc,opencontainers/runc,jhjeong-kr/runc,zenlinTechnofreak/runc,w4ngyi/libcontainer,mYmNeo/runc,fabiokung/runc,xiaochenshen/runc,whosthatknocking/runc,keloyang/runc,rajasec/runc,runcom/runc,willmtemple/runc,shishir-a412ed/runc,WeiZhang555/runc,ZJU-SEL/runc,meihuabo/runc,cyphar/runc,albertoleal/runc,mheon/runc,markllama/runc,WeiZhang555/runc,maxamillion/runc,avagin/runc,runcom/libcontainer,abduld/runc,mYmNeo/runc,intfrr/runc,opencontainers/runc,hqhq/libcontainer,balajibr/runc,wcwxyz/runc,InformatiQ/runc,WeiZhang555/runc,boucher/runc,kolyshkin/runc,jwuwork/runc,ekuric/runc,wcwxyz/runc,carlye566/runc,docker/runc,markllama/runc,keloyang/runc,ycaihua/libcontainer,rajasec/runc,crosbymichael/runc,mapk0y/runc,jhowardmsft/runc,crosbymichael/runc,subuser-security/runc,han-wang/runc,talwai/runc,mrunalp/runc,hqhq/runc,zhangyancoder/libcontainer,xiaochenshen/runc