Add forklift service

[nickgerace]

Description

This PR adds the forklift service, which "forklifts" data into a data warehouse. Right now, it only "forklifts" one set of data: billing events. That functionality is "opt-in" and the layered load config for the forklift instance must be used to enable data warehouse stream client use.

In addition to these changes, we are publishing fully-formed billing events over NATS Jetstream in four scenarios: the HEAD change set's pointer has changed, the HEAD change set's status has changed, a resource has been created, and a resource has been deleted.

Additional Changes

• Transform billing-events-server into forklift-server
• Use and spawn forklift-server in anything using the dal test harness
• Move billing events publishing to its own module in the dal
• Move and rename jetstreams streams wrapper to its own module in the dal
• Remove unused and aged dal integration tests
• Create resource metadata and change set status modules with corresponding structs and enums in si-events-rs
• Adjust relevant .github files

[nickgerace]

This PR is taking on a slightly different form and introducing the new "forklift" service. Still hasn't come out of a drafts yet though.

[nickgerace]

Adding @sprutton1 and @johnrwatson to review since this a new service.

[nickgerace]

These two minor/cosmetic changes I want to make before merging, as a heads up, but this is still good to go.