以 Homebrew Git 取代 MacOS 內建 Git 並更新

1. Install Homebrew

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

2. Install Git

brew install git

3. 取代Mac 原有GIT

brew link --overwrite git

4. 以後Upgrade

brew upgrade Git