Use relative module path for both UBI and Alpine builds

[shaun-nx]

Overview

When running NGINX on Alpine, the default directory for NGINX libraries is /usr/lib/nginx/modues
Other base images, like UBI, use /usr/lib64/nginx/moudles

By default, NGINX will create a symlink from /etc/nginx/modules to the appropriate modules dir based on the base image use.

For Alpine

lrwxrwxrwx 1 nginx nginx /etc/nginx/modules -> /usr/lib/nginx/modules

For UBI

lrwxrwxrwx 1 nginx nginx /etc/nginx/modules -> /usr/lib64/nginx/modules

This change aims to ensure we use moduels/<module_name> for all references to modules to ensure NGINX behaves consistently across difference base images