When there's no connection to pg, the following error happens
when running --dump-schema:

postgrest: user error (Pattern match failure in do expression at
main/Main.hs:361:5-14)

Now it shows a regular "could not connect to server.." error.

Allows configuring postgrest from the db by setting config parameters
on the connection role. For example:

ALTER ROLE postgrest_test_authenticator
SET pgrst.jwt-secret = "REALLYREALLYREALLYREALLYVERYSAFE"

The above wWill set the `jwt-secret` config option accordingly.

SUPERUSER privileges are required for ALTERing role settings,
so this might not work on some cloud-managed databases.

This feature is enabled by default, for disabling it you can add the
following to the config file:

db-load-guc-config = false

Enables reloading the config by doing:
NOTIFY pgrst, 'reload config'

Adds an alias for reloading the schema cache:
NOTIFY pgrst, 'reload schema'