Release of pg_dbms_stats for PostgreSQL 15

[Lerm]

Hi,

PostgreSQL 15 has already gone through its second point release for now, so I'd like to ask if there are any plans for the pg_dbms_stats version for this release?

[Lerm]

Just in case, here is my attempt to make PG15-compatible version, with list of discovered problems and proposed fixes: #10. Hope it may be useful for creating official release of pg_dmbs_stats for PG15.