Cache NO ACTION foreign keys separately from RESTRICT foreign keys

Cache NO ACTION foreign keys separately from RESTRICT foreign keys

Now that we generate different SQL for temporal NO ACTION vs RESTRICT
foreign keys, we should cache their query plans with different keys.
Since the key also includes the constraint oid, this shouldn't be
necessary, but we have been seeing build farm failures that suggest we
might be sometimes using a cached NO ACTION plan to implement a RESTRICT
constraint.

Author: Paul A. Jungwirth 
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com