Implement and Deploy Phase 2 code path routing logic

Context

After the completion of Phase 1, 100% of new repositories will be routed to the database. Therefore, we need to switch from Phase 1 Routing to Phase 2 Routing

Problem

The phase 2 routing logic has already been described and is simpler to implement than the current phase 1 logic; however, this logic effects each incoming API request and is crucial now only for the beginning of phase 2, but also ensuring that 100% of new repositories are appropriately routed to the database.

Proposal

Given this significant change in logic, it's probably best to release a version of the registry which contains only the MR which implements this change, so that we can observe it in production and cleanly roll it back if there are any issues.