services: Use .env file for docker-compose

Summary:
This replaces the services_config.sh script.

https://linear.app/comm/issue/ENG-778/use-docker-compose-environment-file

Test Plan: Run launch scripts

Reviewers: karol-bisztyga, ashoat, geekbrother, varun

Reviewed By: karol-bisztyga, ashoat, geekbrother

Subscribers: palys-swm, Adrian, atul, benschac

Differential Revision: https://phabricator.ashoat.com/D3233