Enable gzip on nginx proxy

[lordrip]

Please describe the task that needs to be done

At the moment, gzip is not enabled in the nginx config, and this affects how much data is transferred over the wire, especially for the catalog.

The goal it's to enable gzip and brotli compression algorithms to reduce the amount of data being transferred.

[lordrip]

At the time of writing, brotli is not included in nginx, meaning that we would need to install it separately.

• Brotli support for nginx alpine image nginxinc/docker-nginx#371 (comment)
• https://github.com/nginxinc/docker-nginx/tree/master/modules