Use lower connection pool defaults ⬇️

[lovelydinosaur]

Right now we're using the default settings for the connection pool with asyncpg. This ends up being 10 connections per worker process. We're running 2 worker processes, so holding onto 20 database connections. This just happens to also be the maximum number of allowed postgres connection against a Hobby-tier database, so when we run migrations we're now getting a failure with "Too many connections".