[COR-842] Spike: Determine what it means to certify an extension

[coredb-service-user]

Implement a system for 'certifying' Postgres extensions. This will likely involve some spike time as we think about what makes an extension 'certified'.

_{From SyncLinear.com | COR-842}

[coredb-service-user]

Samay mentioned:

As we move towards certification of extensions, we should also run the entire Postgres core test suite with extension binary installed to make sure it doesn’t mess anything up in core Postgres functionality.