docker安装gd库扩展

参考：https://blog.csdn.net/qq_25194685/article/details/90407929

apt update  #更新软件源
apt install -y libwebp-dev libjpeg-dev libpng-dev libfreetype6-dev #安装各种库
docker-php-source extract #解压源码
cd /usr/src/php/ext/gd  #gd源码文件夹
docker-php-ext-configure gd --with-webp-dir=/usr/include/webp --with-jpeg-dir=/usr/include --with-png-dir=/usr/include --with-freetype-dir=/usr/include/freetype2   #准备编译
docker-php-ext-install gd   #编译安装
php -m | grep gd

这个搞了大半天了，特地记下来