The need for this was foreseen long ago, but when record_eq
actually became hashable (in commit 01e658fa), we missed updating
this spot.

Per bug #17363 from Elvis Pranskevichus.  Back-patch to v14 where
the faulty commit came in.

Discussion: https://postgr.es/m/17363-f6d42fd0d726be02@postgresql.org