fix 'which' when global shim dir doesn't exist
fix 'which' when global shim dir doesn't exist

toxeus/scoop,rivy/ladle,rivy/scoop,Congee/scoop,vidarkongsli/scoop,r15ch13/scoop,pacificcoast/scoop,coonce/scoop,bpollack/scoop,barohatoum/scoop,berwyn/scoop,DarylWright/scoop,Cyianor/scoop,guillermooo-forks/scoop,damnhandy/scoop,saildata/scoop,dennislloydjr/scoop,pacificcoast/scoop,deepwaterdiver/scoop,vinaynambiar/lukesampson-,deepwaterdiver/scoop,seonho/scoop,rodericktech/scoop,ErnWong/scoop,nikolasd/scoop,reelsense/scoop,systemexitzero/scoop,dennislloydjr/scoop,barohatoum/scoop,lukesampson/scoop,huncrys/scoop,bcomnes/scoop,deevus/scoop-powershell2,devoncarew/scoop,moigagoo/scoop,huncrys/scoop,rmyorston/scoop,kodybrown/scoop,rivy/ladle,rasa/scoop,yunspace/scoop,nueko/scoop,ShwoognationHQ/scoop