Remove the queryid_stat_statements field.

Remove the queryid_stat_statements field.

With pg14 and above core postgres can compute a queryid without any
external extension, so we can simply rely on it.  We do so by asking
for the core to compute a queryid if users allow it.  Note that if
users explicitly disable compute_query_id, we will obey and not record
anything.

For previous versions, automatically detect if a queryid is computed
by some external extensions or not.  If yes, use it as the key queryid
otherwise fallback on internal queryid calculation.