linkage_checker.rb: fix indentation in `display_items`
linkage_checker.rb: fix indentation in `display_items`

Co-authored-by: Mike McQuaid <a17fed27eaa842282862ff7c1b9c8395a26ac320@mikemcquaid.com>
EricFromCanada/brew,nandub/brew,claui/brew,mahori/brew,Homebrew/brew,MikeMcQuaid/brew,JCount/brew,EricFromCanada/brew,reitermarkus/brew,vitorgalvao/brew,reitermarkus/brew,reitermarkus/brew,mahori/brew,vitorgalvao/brew,sjackman/homebrew,nandub/brew,EricFromCanada/brew,claui/brew,Homebrew/brew,Homebrew/brew,MikeMcQuaid/brew,vitorgalvao/brew,konqui/brew,JCount/brew,claui/brew,MikeMcQuaid/brew,nandub/brew,sjackman/homebrew,konqui/brew,nandub/brew,mahori/brew,claui/brew,MikeMcQuaid/brew,Homebrew/brew,mahori/brew,JCount/brew,sjackman/homebrew,sjackman/homebrew,EricFromCanada/brew,JCount/brew,vitorgalvao/brew,konqui/brew,reitermarkus/brew,konqui/brew