brew.sh: remove unused variable.
brew.sh: remove unused variable.

As of #4377 this is no longer used.

EricFromCanada/brew,MikeMcQuaid/brew,Linuxbrew/brew,claui/brew,nandub/brew,mahori/brew,EricFromCanada/brew,maxim-belkin/brew,vitorgalvao/brew,Linuxbrew/brew,konqui/brew,EricFromCanada/brew,claui/brew,konqui/brew,sjackman/homebrew,claui/brew,sjackman/homebrew,reitermarkus/brew,nandub/brew,EricFromCanada/brew,Homebrew/brew,Homebrew/brew,reitermarkus/brew,mahori/brew,claui/brew,vitorgalvao/brew,mahori/brew,MikeMcQuaid/brew,JCount/brew,konqui/brew,vitorgalvao/brew,konqui/brew,Homebrew/brew,reitermarkus/brew,maxim-belkin/brew,mahori/brew,MikeMcQuaid/brew,Linuxbrew/brew,Linuxbrew/brew,JCount/brew,JCount/brew,nandub/brew,nandub/brew,JCount/brew,vitorgalvao/brew,maxim-belkin/brew,DomT4/brew,DomT4/brew,sjackman/homebrew,ilovezfs/brew,ilovezfs/brew,DomT4/brew,reitermarkus/brew,ilovezfs/brew,sjackman/homebrew,Homebrew/brew,DomT4/brew,MikeMcQuaid/brew