Run Tests in GitHub Actions using the Production DEA ODC Database

[omad]

Proposed changes

This PR makes use of some AWS infrastructure I've setup to enable GitHub Actions to connect to the Production DEA ODC PostgreSQL database.

This will allow us to run automated tests of all our code and notebooks using real data, without having to maintain an extracted subset, or any other awkward workarounds.

It uses the existing OIDC authentication to AWS to create a temporary network tunnel using Basti.

Still to do

This PR only contains a framework and setup for setting up this connection and running the tests.

Still to do is:

• Removing or merging the other GitHub Actions running tests.
• Removing sample data and references that are being used.
• Trying to speed things up so it doesn't take an hour to run.