[Homebrew] homebrew-core is a sh

使用Homebrew报错
按照提示执行git -C /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core fetch --unshallow又报远端意外挂起😯

于是直接删了 homebrew-core，再 brew update：
rm -rf /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core

完事儿～