System Test: add coverage for Galexie and Datastore consumer

[sreuland]

What problem does your feature solve?

Galexie publisher and Datastore consumer are not included in the test coverage for a given configured target network stack.

What would you like to see?

A new test that runs:

• Galexie publisher configured to the test's configured target network and a GCS or AWS S3 Datastore.
• a go client stub program which uses BSB and consumes from the GCP or AWS datastore endpoint.
• The test invokes a contract fn that emits an event, could be custom contract event or just a SAC transfer/mint.
• The test asserts the go client program running BSB consumer receives the expected meta containing the event related to the contract invocation from the GCS or AWS Datastore..

What alternatives are there?

[leighmcculloch]

I think we should add galexie to quickstart rather than add it as an additional service here.

[sreuland]

Yes, that sounds good, less for system-test to replicate and more functionality available purely in quickstart in any case.