Use Dir.mktmpdir in doctor
Use Dir.mktmpdir in doctor

This matches how we create temporary directories elsewhere.

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