Fix method redefinition warning
Fix method redefinition warning

test_defined? gets defined in the method_added hook.

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