brew.rb: remove executable bit and shebang
brew.rb: remove executable bit and shebang

Because `brew.rb` should never be invoked directly, remove executable
bit and shebang to make that more obvious.

Closes Homebrew/homebrew#48816.

Signed-off-by: Martin Afanasjew <54669547a225ff20cba8b75a4adca540eef25858@afanasjew.de>

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