Remove unused `popen_read_text` method.
Remove unused `popen_read_text` method.

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