如何在docker image richarvey / nginx-php-fpm上安装php56-pecl-imagick

I am trying to get Imagick installed on this docker image: richarvey/nginx-php-fpm:php5

I am trying to debug some issues, hence the old version.

Normally on Redhat i'll run the yum cmd to execute:

sudo yum install -y php56-pecl-imagick

Here's the original repo for that install. https://github.com/richarvey/nginx-php-fpm