Stable GraphQL API versions to backfill enum values

Our stable API versions will retroactively add values into GraphQL Enum types, making them non-exhaustive going forward. This assures that new application data values can be represented in older API versions, which provides better stability.

While this is a non-breaking change, it can cause disruptions to development toolchains. We recommend that you periodically refresh introspection caches, and integrate enums into your application logic with a catch-all that anticipates unknown cases.

For more information, see https://shopify.dev/docs/api/usage/versioning#stable-api-versions.