cc: always filter flags on deps.
cc: always filter flags on deps.

This has been tested by `brew test-bot` since March and there’s been no
issues so let’s turn it on by default.

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