Mismatch with DB URL for Creating and Flushing

[judtinzhang]

For some reason on prod, I needed to change the DB protocol to postgresql+asyncpg for creating the table, but for flushing I needed to change it back to just postgresql. We need to figure out a way to only require one of these protocols. I'd imagine this can be as easy as making creating the table a synchronous operation, since it is a one-time thing anyways