pgsql: Fix DDL deparse of CREATE OPERATOR CLASS

Fix DDL deparse of CREATE OPERATOR CLASS

When an implicit operator family is created, it wasn't getting reported.
Make it do so.

This has always been missing.  Backpatch to 10.

Author: Masahiko Sawada <sawada.mshk@gmail.com>
Reported-by: Leslie LEMAIRE <leslie.lemaire@developpement-durable.gouv.fr>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Michael Paquiër <michael@paquier.xyz>
Discussion: https://postgr.es/m/f74d69e151b22171e8829551b1159e77@developpement-durable.gouv.fr

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/6029861916e8e2c0155c332c10f182a22619c663

Modified Files
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src/backend/commands/opclasscmds.c                    | 19 ++++++++++++++-----
src/backend/tcop/utility.c                            |  6 ++++++
.../modules/test_ddl_deparse/expected/opfamily.out    |  1 +
src/test/regress/expected/event_trigger.out           |  5 +++++
src/test/regress/sql/event_trigger.sql                |  4 ++++
5 files changed, 30 insertions(+), 5 deletions(-)