listen silently fails on a read replica

[steve-chavez]

Read replicas fail on LISTEN:

postgres=# LISTEN pgrst;
ERROR:  cannot execute LISTEN during recovery

postgres=# select pg_is_in_recovery();
 pg_is_in_recovery 
-------------------
 t
(1 row)

# Also see https://stackoverflow.com/questions/70293290/can-you-perform-listen-unlisten-on-a-postgresql-read-replica

This currently fails silently on hasql-notifications, due to listen ignoring the error (void):

hasql-notifications/src/Hasql/Notifications.hs

Line 120 in c8f4956

execListen pqCon = void $ PQ.exec pqCon $ T.encodeUtf8 $ "LISTEN " <> fromPgIdentifier channel

Note: UNLISTEN doesn't fail on the replica, but it would still be good to not ignore the error there too.

[diogob]

thanks for the report @steve-chavez , will fix it.