Update gstg-base-db-geo-postgres.json Chef role to have correct attributes and run_list

The staging Geo all-in-one Secondary geo-dr-01-db-gstg.c.gitlab-staging-1.internal has a bare bones Chef role associated to it - https://ops.gitlab.net/gitlab-cookbooks/chef-repo/blob/master/roles/gstg-base-db-geo-postgres.json. Currently, gstg-base-db-geo-postgres.json only configures the host to be a DB type node but we need all the necessary attributes added / run_list updated to make it an all-in-one node so it can run the following, e.g.

• DB (both main PostgreSQL and Geo tracking DB)
• redis
• sidekiq
• unicorn
• gitlab-workhorse
• nginx
• etc..