Avoid unnecessarily setting env variables on the lint build
Avoid unnecessarily setting env variables on the lint build

The relevent env variables are set for the matrix builds, and are irrelevant
to the lint build. By default the first matrix entry is applied.

"Each job included in jobs.include inherits the first value of the array that defines a matrix dimension."
https://docs.travis-ci.com/user/build-stages/#Build-Stages-and-Build-Matrix-Expansion

mm-s/bitcoin,jonasschnelli/bitcoin,practicalswift/bitcoin,midnightmagic/bitcoin,guncoin/guncoin,apoelstra/bitcoin,vmp32k/litecoin,mruddy/bitcoin,MeshCollider/bitcoin,achow101/bitcoin,pstratem/bitcoin,ericshawlinux/bitcoin,Christewart/bitcoin,mitchellcash/bitcoin,GroestlCoin/bitcoin,rnicoll/dogecoin,wellenreiter01/Feathercoin,AkioNak/bitcoin,GlobalBoost/GlobalBoost,wellenreiter01/Feathercoin,yenliangl/bitcoin,GroestlCoin/bitcoin,Xekyo/bitcoin,monacoinproject/monacoin,droark/bitcoin,lbryio/lbrycrd,CryptArc/bitcoin,monacoinproject/monacoin,qtumproject/qtum,Kogser/bitcoin,sipsorcery/bitcoin,achow101/bitcoin,practicalswift/bitcoin,particl/particl-core,GlobalBoost/GlobalBoost,domob1812/namecore,rnicoll/bitcoin,jambolo/bitcoin,afk11/bitcoin,andreaskern/bitcoin,fujicoin/fujicoin,litecoin-project/litecoin,droark/bitcoin,monacoinproject/monacoin,particl/particl-core,practicalswift/bitcoin,qtumproject/qtum,JeremyRubin/bitcoin,nikkitan/bitcoin,MarcoFalke/bitcoin,untrustbank/litecoin,jonasschnelli/bitcoin,jamesob/bitcoin,jambolo/bitcoin,rnicoll/bitcoin,lateminer/bitcoin,FeatherCoin/Feathercoin,jlopp/statoshi,OmniLayer/omnicore,domob1812/bitcoin,yenliangl/bitcoin,vertcoin/vertcoin,instagibbs/bitcoin,BTCGPU/BTCGPU,bitcoinknots/bitcoin,fanquake/bitcoin,RHavar/bitcoin,domob1812/bitcoin,GroestlCoin/bitcoin,instagibbs/bitcoin,RHavar/bitcoin,ElementsProject/elements,bitcoinknots/bitcoin,practicalswift/bitcoin,kallewoof/bitcoin,Kogser/bitcoin,r8921039/bitcoin,ajtowns/bitcoin,wellenreiter01/Feathercoin,ahmedbodi/vertcoin,Kogser/bitcoin,GroestlCoin/GroestlCoin,mruddy/bitcoin,apoelstra/bitcoin,instagibbs/bitcoin,mruddy/bitcoin,sstone/bitcoin,bitcoinknots/bitcoin,Kogser/bitcoin,Bushstar/UFO-Project,GlobalBoost/GlobalBoost,jamesob/bitcoin,fanquake/bitcoin,OmniLayer/omnicore,sipsorcery/bitcoin,myriadteam/myriadcoin,bitcoinsSG/bitcoin,jambolo/bitcoin,BTCGPU/BTCGPU,kazcw/bitcoin,ajtowns/bitcoin,lateminer/bitcoin,GroestlCoin/GroestlCoin,MarcoFalke/bitcoin,particl/particl-core,pataquets/namecoin-core,qtumproject/qtum,DigitalPandacoin/pandacoin,jlopp/statoshi,sipsorcery/bitcoin,prusnak/bitcoin,ajtowns/bitcoin,dscotese/bitcoin,bespike/litecoin,anditto/bitcoin,Flowdalic/bitcoin,peercoin/peercoin,untrustbank/litecoin,GlobalBoost/GlobalBoost,tecnovert/particl-core,thrasher-/litecoin,ElementsProject/elements,tecnovert/particl-core,digibyte/digibyte,achow101/bitcoin,namecoin/namecore,n1bor/bitcoin,myriadcoin/myriadcoin,digibyte/digibyte,midnightmagic/bitcoin,Xekyo/bitcoin,Bushstar/UFO-Project,GlobalBoost/GlobalBoost,myriadteam/myriadcoin,MarcoFalke/bitcoin,mitchellcash/bitcoin,yenliangl/bitcoin,namecoin/namecoin-core,gjhiggins/vcoincore,ElementsProject/elements,n1bor/bitcoin,JeremyRubin/bitcoin,jonasschnelli/bitcoin,mitchellcash/bitcoin,tjps/bitcoin,qtumproject/qtum,cdecker/bitcoin,achow101/bitcoin,lbryio/lbrycrd,prusnak/bitcoin,qtumproject/qtum,guncoin/guncoin,mm-s/bitcoin,untrustbank/litecoin,jamesob/bitcoin,jnewbery/bitcoin,domob1812/bitcoin,ericshawlinux/bitcoin,tecnovert/particl-core,apoelstra/bitcoin,domob1812/bitcoin,fanquake/bitcoin,Flowdalic/bitcoin,pataquets/namecoin-core,wellenreiter01/Feathercoin,AkioNak/bitcoin,tecnovert/particl-core,myriadcoin/myriadcoin,mm-s/bitcoin,ajtowns/bitcoin,bitcoin/bitcoin,h4x3rotab/BTCGPU,vertcoin/vertcoin,Christewart/bitcoin,wellenreiter01/Feathercoin,bitcoinknots/bitcoin,namecoin/namecore,mitchellcash/bitcoin,bitcoin/bitcoin,myriadteam/myriadcoin,pataquets/namecoin-core,Sjors/bitcoin,cdecker/bitcoin,Xekyo/bitcoin,tjps/bitcoin,untrustbank/litecoin,domob1812/namecore,thrasher-/litecoin,droark/bitcoin,prusnak/bitcoin,anditto/bitcoin,DigitalPandacoin/pandacoin,myriadteam/myriadcoin,jnewbery/bitcoin,vmp32k/litecoin,fujicoin/fujicoin,Christewart/bitcoin,Xekyo/bitcoin,vmp32k/litecoin,jonasschnelli/bitcoin,n1bor/bitcoin,mm-s/bitcoin,CryptArc/bitcoin,mruddy/bitcoin,gjhiggins/vcoincore,OmniLayer/omnicore,tecnovert/particl-core,lbryio/lbrycrd,myriadcoin/myriadcoin,afk11/bitcoin,ajtowns/bitcoin,gjhiggins/vcoincore,alecalve/bitcoin,Bushstar/UFO-Project,EthanHeilman/bitcoin,tecnovert/particl-core,qtumproject/qtum,peercoin/peercoin,GlobalBoost/GlobalBoost,jtimon/bitcoin,OmniLayer/omnicore,Flowdalic/bitcoin,midnightmagic/bitcoin,fujicoin/fujicoin,Kogser/bitcoin,guncoin/guncoin,digibyte/digibyte,ahmedbodi/vertcoin,CryptArc/bitcoin,sstone/bitcoin,monacoinproject/monacoin,gjhiggins/vcoincore,guncoin/guncoin,instagibbs/bitcoin,Xekyo/bitcoin,alecalve/bitcoin,jtimon/bitcoin,kazcw/bitcoin,mm-s/bitcoin,AkioNak/bitcoin,lbryio/lbrycrd,EthanHeilman/bitcoin,andreaskern/bitcoin,guncoin/guncoin,EthanHeilman/bitcoin,kallewoof/bitcoin,instagibbs/bitcoin,digibyte/digibyte,lateminer/bitcoin,nikkitan/bitcoin,Kogser/bitcoin,sstone/bitcoin,jonasschnelli/bitcoin,anditto/bitcoin,jlopp/statoshi,BTCGPU/BTCGPU,rnicoll/bitcoin,dscotese/bitcoin,bitcoin/bitcoin,myriadteam/myriadcoin,MeshCollider/bitcoin,ericshawlinux/bitcoin,digibyte/digibyte,andreaskern/bitcoin,sipsorcery/bitcoin,DigitalPandacoin/pandacoin,dscotese/bitcoin,jambolo/bitcoin,Christewart/bitcoin,MarcoFalke/bitcoin,namecoin/namecoin-core,apoelstra/bitcoin,MarcoFalke/bitcoin,vertcoin/vertcoin,mitchellcash/bitcoin,vmp32k/litecoin,litecoin-project/litecoin,rnicoll/bitcoin,GroestlCoin/bitcoin,namecoin/namecore,CryptArc/bitcoin,jlopp/statoshi,ajtowns/bitcoin,EthanHeilman/bitcoin,tjps/bitcoin,vertcoin/vertcoin,ericshawlinux/bitcoin,MeshCollider/bitcoin,n1bor/bitcoin,fujicoin/fujicoin,achow101/bitcoin,bespike/litecoin,bitcoin/bitcoin,pstratem/bitcoin,Kogser/bitcoin,myriadcoin/myriadcoin,sstone/bitcoin,thrasher-/litecoin,cdecker/bitcoin,h4x3rotab/BTCGPU,nikkitan/bitcoin,thrasher-/litecoin,MeshCollider/bitcoin,Sjors/bitcoin,pataquets/namecoin-core,Flowdalic/bitcoin,myriadcoin/myriadcoin,AkioNak/bitcoin,afk11/bitcoin,domob1812/namecore,alecalve/bitcoin,jnewbery/bitcoin,jnewbery/bitcoin,midnightmagic/bitcoin,prusnak/bitcoin,ahmedbodi/vertcoin,Bushstar/UFO-Project,domob1812/namecore,bitcoinsSG/bitcoin,Sjors/bitcoin,yenliangl/bitcoin,FeatherCoin/Feathercoin,r8921039/bitcoin,ElementsProject/elements,Kogser/bitcoin,cdecker/bitcoin,jlopp/statoshi,kazcw/bitcoin,kallewoof/bitcoin,Sjors/bitcoin,ElementsProject/elements,JeremyRubin/bitcoin,pataquets/namecoin-core,namecoin/namecore,guncoin/guncoin,vmp32k/litecoin,jambolo/bitcoin,Bushstar/UFO-Project,lateminer/bitcoin,domob1812/namecore,alecalve/bitcoin,domob1812/bitcoin,rnicoll/bitcoin,RHavar/bitcoin,Kogser/bitcoin,EthanHeilman/bitcoin,afk11/bitcoin,FeatherCoin/Feathercoin,particl/particl-core,pstratem/bitcoin,vmp32k/litecoin,anditto/bitcoin,particl/particl-core,vertcoin/vertcoin,tjps/bitcoin,cdecker/bitcoin,jamesob/bitcoin,jlopp/statoshi,Kogser/bitcoin,andreaskern/bitcoin,AkioNak/bitcoin,CryptArc/bitcoin,JeremyRubin/bitcoin,MeshCollider/bitcoin,afk11/bitcoin,achow101/bitcoin,bitcoinsSG/bitcoin,h4x3rotab/BTCGPU,droark/bitcoin,lateminer/bitcoin,h4x3rotab/BTCGPU,DigitalPandacoin/pandacoin,fanquake/bitcoin,sstone/bitcoin,ericshawlinux/bitcoin,alecalve/bitcoin,BTCGPU/BTCGPU,anditto/bitcoin,kallewoof/bitcoin,rnicoll/dogecoin,jamesob/bitcoin,nikkitan/bitcoin,Christewart/bitcoin,yenliangl/bitcoin,n1bor/bitcoin,nikkitan/bitcoin,h4x3rotab/BTCGPU,rnicoll/dogecoin,ahmedbodi/vertcoin,sipsorcery/bitcoin,GroestlCoin/GroestlCoin,Sjors/bitcoin,apoelstra/bitcoin,r8921039/bitcoin,ElementsProject/elements,fanquake/bitcoin,Flowdalic/bitcoin,domob1812/namecore,sstone/bitcoin,r8921039/bitcoin,practicalswift/bitcoin,MeshCollider/bitcoin,cdecker/bitcoin,Bushstar/UFO-Project,untrustbank/litecoin,namecoin/namecoin-core,peercoin/peercoin,r8921039/bitcoin,pstratem/bitcoin,jambolo/bitcoin,andreaskern/bitcoin,GroestlCoin/bitcoin,GroestlCoin/GroestlCoin,bespike/litecoin,bitcoin/bitcoin,mitchellcash/bitcoin,bespike/litecoin,bespike/litecoin,thrasher-/litecoin,FeatherCoin/Feathercoin,Kogser/bitcoin,prusnak/bitcoin,pstratem/bitcoin,Christewart/bitcoin,r8921039/bitcoin,bitcoinknots/bitcoin,pstratem/bitcoin,rnicoll/dogecoin,JeremyRubin/bitcoin,CryptArc/bitcoin,yenliangl/bitcoin,RHavar/bitcoin,FeatherCoin/Feathercoin,mruddy/bitcoin,litecoin-project/litecoin,monacoinproject/monacoin,DigitalPandacoin/pandacoin,h4x3rotab/BTCGPU,namecoin/namecoin-core,BTCGPU/BTCGPU,kallewoof/bitcoin,ahmedbodi/vertcoin,bitcoinsSG/bitcoin,mm-s/bitcoin,myriadteam/myriadcoin,RHavar/bitcoin,qtumproject/qtum,myriadcoin/myriadcoin,gjhiggins/vcoincore,bitcoinsSG/bitcoin,particl/particl-core,RHavar/bitcoin,sipsorcery/bitcoin,wellenreiter01/Feathercoin,instagibbs/bitcoin,rnicoll/dogecoin,midnightmagic/bitcoin,namecoin/namecore,fujicoin/fujicoin,MarcoFalke/bitcoin,namecoin/namecore,andreaskern/bitcoin,FeatherCoin/Feathercoin,nikkitan/bitcoin,bespike/litecoin,EthanHeilman/bitcoin,dscotese/bitcoin,GlobalBoost/GlobalBoost,afk11/bitcoin,midnightmagic/bitcoin,kallewoof/bitcoin,Xekyo/bitcoin,alecalve/bitcoin,lbryio/lbrycrd,droark/bitcoin,AkioNak/bitcoin,rnicoll/bitcoin,litecoin-project/litecoin,OmniLayer/omnicore,mruddy/bitcoin,monacoinproject/monacoin,lateminer/bitcoin,GroestlCoin/GroestlCoin,dscotese/bitcoin,Flowdalic/bitcoin,GroestlCoin/GroestlCoin,ahmedbodi/vertcoin,namecoin/namecoin-core,tjps/bitcoin,bitcoinsSG/bitcoin,peercoin/peercoin,anditto/bitcoin,jnewbery/bitcoin,prusnak/bitcoin,DigitalPandacoin/pandacoin,OmniLayer/omnicore,pataquets/namecoin-core,kazcw/bitcoin,JeremyRubin/bitcoin,tjps/bitcoin,peercoin/peercoin,Kogser/bitcoin,gjhiggins/vcoincore,fanquake/bitcoin,n1bor/bitcoin,thrasher-/litecoin,fujicoin/fujicoin,bitcoin/bitcoin,vertcoin/vertcoin,jtimon/bitcoin,digibyte/digibyte,jtimon/bitcoin,droark/bitcoin,litecoin-project/litecoin,GroestlCoin/bitcoin,jamesob/bitcoin,practicalswift/bitcoin,dscotese/bitcoin,kazcw/bitcoin,untrustbank/litecoin,lbryio/lbrycrd,jtimon/bitcoin,domob1812/bitcoin,kazcw/bitcoin,lbryio/lbrycrd,BTCGPU/BTCGPU,apoelstra/bitcoin,jtimon/bitcoin,ericshawlinux/bitcoin,peercoin/peercoin,litecoin-project/litecoin,namecoin/namecoin-core