Fix up docker-compose file

[bilbof]

This fixes a couple of issues with the Docker compose demo. Setting the domain and password enables the web server to connect to mysql.

Steps to reproduce/test fix:

docker compose up

Errors seen:

iris-web_1    | DB not up yet. Waiting a few seconds..
iris-web_1    | Waited too long for DB to come up. Bailing.

Enter password: ERROR 1045 (28000): Access denied for user 'root'@'172.18.0.3' (using password: YES)

Following this I needed to run these bootstrapping commands:

docker exec -it $(docker ps -f name=iris_iris-web_1 -q) bash

mysql -u root --host mysql -p < ./db/schema_0.sql
mysql -u root --host mysql -p -o iris < ./db/dummy_data.sql