Fix bug preventing interactive prompt for host string from working correctly.
Fix bug preventing interactive prompt for host string from working correctly.

Turns out I missed a spot when rearranging the host-related env var names.

opavader/fabric,rane-hs/fabric-py3,ploxiln/fabric,bspink/fabric,bitmonk/fabric,felix-d/fabric,xLegoz/fabric,mathiasertl/fabric,simon-engledew/fabric,pashinin/fabric,cmattoon/fabric,ericholscher/fabric,raimon49/fabric,elijah513/fabric,itoed/fabric,akaariai/fabric,sdelements/fabric,SamuelMarks/fabric,likesxuqiang/fabric,hrubi/fabric,getsentry/fabric,tekapo/fabric,pgroudas/fabric,TarasRudnyk/fabric,fernandezcuesta/fabric,kmonsoor/fabric,rodrigc/fabric,MjAbuz/fabric,qinrong/fabric,rbramwell/fabric,cgvarela/fabric,amaniak/fabric,jaraco/fabric,kxxoling/fabric,bitprophet/fabric,askulkarni2/fabric,StackStorm/fabric,tolbkni/fabric,haridsv/fabric