test: use pgrep for better compatibility
test: use pgrep for better compatibility

pidof is not available on BSD system, while pgrep is present on BSD, Linux and macOS

bitcoin/bitcoin,rnicoll/dogecoin,jnewbery/bitcoin,practicalswift/bitcoin,litecoin-project/litecoin,ElementsProject/elements,namecoin/namecore,sstone/bitcoin,qtumproject/qtum,MarcoFalke/bitcoin,ajtowns/bitcoin,yenliangl/bitcoin,midnightmagic/bitcoin,anditto/bitcoin,kallewoof/bitcoin,sipsorcery/bitcoin,dscotese/bitcoin,jambolo/bitcoin,tecnovert/particl-core,yenliangl/bitcoin,Xekyo/bitcoin,instagibbs/bitcoin,n1bor/bitcoin,dscotese/bitcoin,domob1812/bitcoin,apoelstra/bitcoin,cdecker/bitcoin,namecoin/namecore,bitcoinknots/bitcoin,fujicoin/fujicoin,namecoin/namecore,instagibbs/bitcoin,GroestlCoin/bitcoin,alecalve/bitcoin,particl/particl-core,andreaskern/bitcoin,particl/particl-core,Xekyo/bitcoin,MarcoFalke/bitcoin,EthanHeilman/bitcoin,jamesob/bitcoin,qtumproject/qtum,MarcoFalke/bitcoin,tecnovert/particl-core,pstratem/bitcoin,anditto/bitcoin,Xekyo/bitcoin,cdecker/bitcoin,instagibbs/bitcoin,fujicoin/fujicoin,namecoin/namecore,fanquake/bitcoin,particl/particl-core,bitcoin/bitcoin,fujicoin/fujicoin,midnightmagic/bitcoin,dscotese/bitcoin,particl/particl-core,tecnovert/particl-core,jlopp/statoshi,pstratem/bitcoin,Sjors/bitcoin,pstratem/bitcoin,domob1812/bitcoin,particl/particl-core,qtumproject/qtum,n1bor/bitcoin,namecoin/namecoin-core,jlopp/statoshi,andreaskern/bitcoin,apoelstra/bitcoin,lateminer/bitcoin,GroestlCoin/GroestlCoin,namecoin/namecoin-core,prusnak/bitcoin,MeshCollider/bitcoin,apoelstra/bitcoin,jamesob/bitcoin,achow101/bitcoin,cdecker/bitcoin,achow101/bitcoin,mm-s/bitcoin,GroestlCoin/GroestlCoin,jlopp/statoshi,bitcoinknots/bitcoin,ajtowns/bitcoin,Sjors/bitcoin,Xekyo/bitcoin,lateminer/bitcoin,EthanHeilman/bitcoin,Sjors/bitcoin,jnewbery/bitcoin,namecoin/namecore,prusnak/bitcoin,MarcoFalke/bitcoin,MeshCollider/bitcoin,Xekyo/bitcoin,fanquake/bitcoin,mm-s/bitcoin,MeshCollider/bitcoin,jonasschnelli/bitcoin,achow101/bitcoin,midnightmagic/bitcoin,litecoin-project/litecoin,GroestlCoin/GroestlCoin,sipsorcery/bitcoin,sstone/bitcoin,mruddy/bitcoin,JeremyRubin/bitcoin,ElementsProject/elements,pstratem/bitcoin,domob1812/namecore,pataquets/namecoin-core,EthanHeilman/bitcoin,alecalve/bitcoin,jambolo/bitcoin,jamesob/bitcoin,AkioNak/bitcoin,fujicoin/fujicoin,ElementsProject/elements,anditto/bitcoin,yenliangl/bitcoin,AkioNak/bitcoin,jlopp/statoshi,alecalve/bitcoin,domob1812/namecore,prusnak/bitcoin,practicalswift/bitcoin,jamesob/bitcoin,sstone/bitcoin,practicalswift/bitcoin,n1bor/bitcoin,dscotese/bitcoin,jonasschnelli/bitcoin,cdecker/bitcoin,fanquake/bitcoin,bitcoinknots/bitcoin,bitcoin/bitcoin,namecoin/namecoin-core,pstratem/bitcoin,bitcoinsSG/bitcoin,midnightmagic/bitcoin,dscotese/bitcoin,domob1812/bitcoin,rnicoll/dogecoin,practicalswift/bitcoin,andreaskern/bitcoin,bitcoinsSG/bitcoin,ajtowns/bitcoin,Sjors/bitcoin,practicalswift/bitcoin,pataquets/namecoin-core,litecoin-project/litecoin,namecoin/namecoin-core,fujicoin/fujicoin,namecoin/namecore,AkioNak/bitcoin,jlopp/statoshi,jambolo/bitcoin,anditto/bitcoin,anditto/bitcoin,MarcoFalke/bitcoin,lateminer/bitcoin,mruddy/bitcoin,mruddy/bitcoin,jlopp/statoshi,rnicoll/bitcoin,practicalswift/bitcoin,bitcoinknots/bitcoin,sstone/bitcoin,fujicoin/fujicoin,prusnak/bitcoin,namecoin/namecoin-core,EthanHeilman/bitcoin,alecalve/bitcoin,yenliangl/bitcoin,jambolo/bitcoin,qtumproject/qtum,rnicoll/bitcoin,mm-s/bitcoin,sipsorcery/bitcoin,kallewoof/bitcoin,bitcoin/bitcoin,pstratem/bitcoin,GroestlCoin/GroestlCoin,GroestlCoin/GroestlCoin,midnightmagic/bitcoin,sstone/bitcoin,instagibbs/bitcoin,mruddy/bitcoin,GroestlCoin/bitcoin,lateminer/bitcoin,andreaskern/bitcoin,lateminer/bitcoin,achow101/bitcoin,fanquake/bitcoin,GroestlCoin/GroestlCoin,jonasschnelli/bitcoin,litecoin-project/litecoin,jamesob/bitcoin,tecnovert/particl-core,ajtowns/bitcoin,alecalve/bitcoin,tecnovert/particl-core,apoelstra/bitcoin,cdecker/bitcoin,EthanHeilman/bitcoin,sstone/bitcoin,rnicoll/bitcoin,JeremyRubin/bitcoin,sipsorcery/bitcoin,GroestlCoin/bitcoin,alecalve/bitcoin,AkioNak/bitcoin,rnicoll/bitcoin,AkioNak/bitcoin,sipsorcery/bitcoin,pataquets/namecoin-core,anditto/bitcoin,AkioNak/bitcoin,apoelstra/bitcoin,MeshCollider/bitcoin,qtumproject/qtum,JeremyRubin/bitcoin,jonasschnelli/bitcoin,namecoin/namecoin-core,domob1812/namecore,mruddy/bitcoin,cdecker/bitcoin,kallewoof/bitcoin,ajtowns/bitcoin,domob1812/bitcoin,rnicoll/dogecoin,midnightmagic/bitcoin,litecoin-project/litecoin,pataquets/namecoin-core,mm-s/bitcoin,jnewbery/bitcoin,kallewoof/bitcoin,mruddy/bitcoin,ElementsProject/elements,rnicoll/bitcoin,domob1812/bitcoin,jambolo/bitcoin,Xekyo/bitcoin,jambolo/bitcoin,lateminer/bitcoin,jonasschnelli/bitcoin,domob1812/namecore,mm-s/bitcoin,bitcoinsSG/bitcoin,ajtowns/bitcoin,jnewbery/bitcoin,MarcoFalke/bitcoin,kallewoof/bitcoin,rnicoll/dogecoin,MeshCollider/bitcoin,apoelstra/bitcoin,domob1812/namecore,instagibbs/bitcoin,sipsorcery/bitcoin,jnewbery/bitcoin,rnicoll/bitcoin,pataquets/namecoin-core,JeremyRubin/bitcoin,fanquake/bitcoin,mm-s/bitcoin,JeremyRubin/bitcoin,fanquake/bitcoin,GroestlCoin/bitcoin,bitcoin/bitcoin,n1bor/bitcoin,prusnak/bitcoin,achow101/bitcoin,GroestlCoin/bitcoin,MeshCollider/bitcoin,n1bor/bitcoin,qtumproject/qtum,ElementsProject/elements,achow101/bitcoin,qtumproject/qtum,particl/particl-core,tecnovert/particl-core,instagibbs/bitcoin,pataquets/namecoin-core,EthanHeilman/bitcoin,bitcoin/bitcoin,kallewoof/bitcoin,JeremyRubin/bitcoin,domob1812/bitcoin,andreaskern/bitcoin,andreaskern/bitcoin,n1bor/bitcoin,bitcoinsSG/bitcoin,bitcoinsSG/bitcoin,bitcoinknots/bitcoin,GroestlCoin/bitcoin,domob1812/namecore,prusnak/bitcoin,rnicoll/dogecoin,litecoin-project/litecoin,Sjors/bitcoin,jamesob/bitcoin,yenliangl/bitcoin,bitcoinsSG/bitcoin,yenliangl/bitcoin,dscotese/bitcoin,ElementsProject/elements