Fix OID passed to object-alter hook during ALTER CONSTRAINT
The OID of the constraint is used instead of the OID of the trigger --
an easy mistake to make. Apparently the object-alter hooks are not very
well tested :-(
Backpatch to 12, where this typo was introduced by
578b229718e8
Discussion: https://postgr.es/m/
20210503231633.GA6994@alvherre.pgsql