cmd/unpack: fix Rubocop warnings.
cmd/unpack: fix Rubocop warnings.

reelsense/brew,pseudocody/brew,Linuxbrew/brew,toonetown/homebrew,Linuxbrew/brew,toonetown/homebrew,sjackman/homebrew,JCount/brew,claui/brew,rwhogg/brew,sjackman/homebrew,nandub/brew,vitorgalvao/brew,gregory-nisbet/brew,vitorgalvao/brew,reelsense/brew,mahori/brew,rwhogg/brew,muellermartin/dist,Homebrew/brew,reitermarkus/brew,rwhogg/brew,EricFromCanada/brew,alyssais/brew,MikeMcQuaid/brew,MikeMcQuaid/brew,bfontaine/brew,palxex/brew,jmsundar/brew,JCount/brew,palxex/brew,palxex/brew,JCount/brew,reitermarkus/brew,muellermartin/dist,konqui/brew,claui/brew,pseudocody/brew,mahori/brew,aw1621107/brew,reelsense/brew,DomT4/brew,toonetown/homebrew,hanxue/linuxbrew,amar-laksh/brew_sudo,muellermartin/dist,ilovezfs/brew,claui/brew,zmwangx/brew,DomT4/brew,EricFromCanada/brew,reitermarkus/brew,gregory-nisbet/brew,pseudocody/brew,ilovezfs/brew,ilovezfs/brew,sjackman/homebrew,Linuxbrew/brew,alyssais/brew,hanxue/linuxbrew,hanxue/linuxbrew,Homebrew/brew,konqui/brew,konqui/brew,mahori/brew,bfontaine/brew,Homebrew/brew,jmsundar/brew,gregory-nisbet/brew,aw1621107/brew,bfontaine/brew,JCount/brew,mahori/brew,vitorgalvao/brew,Linuxbrew/brew,EricFromCanada/brew,MikeMcQuaid/brew,amar-laksh/brew_sudo,nandub/brew,DomT4/brew,MikeMcQuaid/brew,zmwangx/brew,claui/brew,nandub/brew,maxim-belkin/brew,tonyg/homebrew,Homebrew/brew,amar-laksh/brew_sudo,EricFromCanada/brew,mgrimes/brew,alyssais/brew,maxim-belkin/brew,maxim-belkin/brew,aw1621107/brew,mgrimes/brew,konqui/brew,tonyg/homebrew,sjackman/homebrew,nandub/brew,DomT4/brew,vitorgalvao/brew,jmsundar/brew,zmwangx/brew,tonyg/homebrew,mgrimes/brew,reitermarkus/brew