Solve the pkg-config error that occurs when installing mysqlclient on macOS sonoma

1. To install mysqlclient with pip on mac, first install homebrew, download the homebrew installation package, and then `brew install mysql pkg-config`. * homebrew .pkg installer：[https://github.com/Homebrew/brew/releases] * How installing Homebrew on macOS Sonoma: [https://bytefrozen.com/post/How installing Homebrew on macOS Sonoma/]