formulary: fix error with absolute alias paths
formulary: fix error with absolute alias paths

Fixes #13883.

MikeMcQuaid/brew,JCount/brew,nandub/brew,Homebrew/brew,Homebrew/brew,MikeMcQuaid/brew,MikeMcQuaid/brew,nandub/brew,Homebrew/brew,JCount/brew,JCount/brew,Homebrew/brew,MikeMcQuaid/brew,nandub/brew,JCount/brew,nandub/brew