HASURA_GRAPHQL_DATABASE_URL no effect

### Version Information

Server Version: 2.7.0

### Environment

Docker compose

### What is the expected behaviour?

The following `docker-compose.yml` should give a running instance with `default` database connection, but it does not.

```yaml
version: '3.6'
services:
postgres:
image: postgres:14
restart: always
volumes:
- db_data:/var/lib/postgresql/data
environment:
POSTGRES_PASSWORD: postgrespassword
graphql-engine:
image: hasura/graphql-engine:v2.7.0.cli-migrations-v3
# volumes:
# - ./hasura/migrations:/hasura-migrations
# - ./hasura/metadata:/hasura-metadata
ports:
- "8080:8080"
depends_on:
- "postgres"
restart: always
environment:
## postgres database to store Hasura metadata
HASURA_GRAPHQL_METADATA_DATABASE_URL: postgres://postgres:postgrespassword@postgres:5432/postgres
## this env var can be used to add the above postgres database to Hasura as a data source. this can be removed/updated based on your needs
# PG_DATABASE_URL: postgres://postgres:postgrespassword@postgres:5432/postgres
HASURA_GRAPHQL_DATABASE_URL: postgres://postgres:postgrespassword@postgres:5432/postgres
## enable the console served by server
HASURA_GRAPHQL_ENABLE_CONSOLE: "true" # set to "false" to disable console
## enable debugging mode. It is recommended to disable this in production
HASURA_GRAPHQL_DEV_MODE: "true"
HASURA_GRAPHQL_ENABLED_LOG_TYPES: startup, http-log, webhook-log, websocket-log, query-log
## uncomment next line to set an admin secret
# HASURA_GRAPHQL_ADMIN_SECRET: myadminsecretkey
volumes:
db_data:

```

### Keywords

* HASURA_GRAPHQL_DATABASE_URL
* PG_DATABASE_URL
* Configuration