feat: use hasql-pool-0.10, add db-pool-max-idletime (#2786)

- new option db-pool-max-idletime limits the maximal idle time of a
  postgresql connection, defaults to 30 seconds
- this essentially restores the db-pool-timeout option from versions
  <=10, with more specific name

src/PostgREST/AppState.hs

@@ -115,6 +115,7 @@ initPool AppConfig{..} =
     configDbPoolSize
     (fromIntegral configDbPoolAcquisitionTimeout)
     (fromIntegral configDbPoolMaxLifetime)
+    (fromIntegral configDbPoolMaxIdletime)
     (toUtf8 configDbUri)
 
 -- | Run an action with a database connection.