Finalize src and testing docker-compose.yaml files to include Keycloak service with our actual implementation

This is essentially a duplicate of iambackend#3, but for the frontend.

I have taken a stab at configuring the docker-compose.yaml files.

These files need to be finalized in a way that suits production. Particularly, for example, when the PantryKeycloak docker compose is run, it mounts the data folder and the entrypoint, as well as the exports directory, so that it can track its data and use it via the entrypoint script. I do not know how this will work in production, when the image being used is from the Docker container registry via the custom build process. Will those folders already be mounted? How will data persist? How should the deployment team actually configure a docker-compose.yaml file to allow for backups/etc.

Side note - the testing yaml file may require some extra attention, adding the Keycloak stuff, then going through the whole thing again to make sure everything (networks, dependencies, etc.) line up with each other. This will also likely require a TestRealm is setup, configured, and exported, so that the test-runner can import a custom test realm to use. This will consist of things like modifying the docker compose file in test runner to import a specific realm file, creating tests that are based on the interactions between IAMFrontend and that realm, etc.