[FEATURE]: Allow asynchronous database settings in drizzle configuration

[mdnorman]

Feature hasn't been suggested before.

• [x] I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

Currently the drizzle configuration requires status configuration for the database credentials. However, there are instances running migrations where the credentials must be generated or retrieved, such as from an AWS secret.

It would be very helpful if the db settings could be a promise.