test: add wait_for_cookie_credentials() to test framework
test: add wait_for_cookie_credentials() to test framework

to be able to ensure the cookie file is written and auth credentials available
when testing CLI/RPC commands before the RPC connection is up.

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