Several issues observed on Postgres 14.1

[NikolayS]

Thanks for the great extension.

Tried it on PG 14.1, and had the following issues:

1. TIMING and BUFFERS are not working – tried to set it everywhere, on both sides, globally – doesn't matter, I don't get those numbers in the pg_query_state output
2. leader_pid is not working as described in README. Maybe there is something that has changed in recent postgres versions (when leader_pid appeared in pg_stat_activity?), but for parallelized queries, pg_query_state always returns a single entry for me -- parallel workers are not displayed. I ended up using this workaround:

    select pid, leader_pid, (select plan from pg_query_state(pid))
    from pg_stat_activity
    where :PID in (pid, leader_pid)  \watch .5